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# Recent Articles in Phys. Rev. B

## Recent articles in Physical Review B

Published: 2017-02-17T14:32:22-05:00

High-temperature and high-pressure phase transitions in uranium

2017-02-17T10:00:00-05:00

Author(s): J. Bouchet and F. Bottin
The phase diagram of uranium has been explored up to 100 GPa and 2000 K by means of ab initio molecular dynamics (AIMD) simulations. The lattice dynamics and energetics of the stable phases observed experimentally in this range of pressure and temperature are studied in this work. The phonon spectra…
[Phys. Rev. B 95, 054113] Published Fri Feb 17, 2017

Local structure of the crystalline and amorphous states of Ga_{2} Te_{3} phase-change alloy without resonant bonding: A combined x-ray absorption and ab initio study

2017-02-17T10:00:00-05:00

Author(s): A. V. Kolobov, P. Fons, M. Krbal, K. Mitrofanov, J. Tominaga, and T. Uruga
Phase-change memories are usually associated with GeTe-Sb_{2}Te_{3} quasibinary alloys, where the large optical contrast between the crystalline and amorphous phases is attributed to the formation of resonant bonds in the crystalline phase, which has a rocksalt-like structure. The recent findings th…
[Phys. Rev. B 95, 054114] Published Fri Feb 17, 2017

Anomalous lattice compression and magnetic ordering in CuO at high pressures: A structural study and first-principles calculations

2017-02-17T10:00:00-05:00

Author(s): D. P. Kozlenko, K. Drużbicki, S. E. Kichanov, E. V. Lukin, H.-P. Liermann, K. V. Glazyrin, and B. N. Savenko
The structural and magnetic properties of multiferroic CuO have been studied by means of neutron and x-ray powder diffraction at pressures up to 11 and 38 GPa, respectively, and by first-principles theoretical calculations. Anomalous lattice compression is observed, with enlargement of the lattice p…
[Phys. Rev. B 95, 054115] Published Fri Feb 17, 2017

Partial breakdown of quantum thermalization in a Hubbard-like model

2017-02-17T10:00:00-05:00

Author(s): James R. Garrison, Ryan V. Mishmash, and Matthew P. A. Fisher

In recent years, physicists have made great strides toward better understanding isolated many-body quantum systems. Already, two distinct phases are well known: systems that are ergodic and thermalize completely, and, by contrast, systems that exhibit many-body localization (MBL) due to a strong disorder potential, which prevents thermalization. It is tempting to wonder whether a phase of matter could exist between the extremes of full thermalization and MBL in a generic, i.e., nonintegrable, isolated many-body quantum system. Here, the authors provide evidence that such a nonergodic phase can be realized in a translationally invariant itinerant electron model, with both charge and spin degrees of freedom. Exact diagonalization calculations on finite system sizes reveal that there exists a “spin band” of nonthermal eigenstates. These states have entanglement entropy that scales as an overall “volume law,” but after a partial measurement of the spin on each site the scaling is modified to an “area law,” thus suggesting the states are not ergodic. These properties and others suggest that this model realizes a new nonthermal phase of matter, known as a quantum disentangled liquid (QDL). The putative existence of this phase has striking implications for the foundations of quantum statistical mechanics.

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[Phys. Rev. B 95, 054204] Published Fri Feb 17, 2017

Spintronic detection of interfacial magnetic switching in a paramagnetic thin film of tris(8-hydroxyquinoline)iron(III)

2017-02-17T10:00:00-05:00

Author(s): Dali Sun, Christopher M. Kareis, Kipp J. van Schooten, Wei Jiang, Gene Siegel, Marzieh Kavand, Royce A. Davidson, William W. Shum, Chuang Zhang, Haoliang Liu, Ashutosh Tiwari, Christoph Boehme, Feng Liu, Peter W. Stephens, Joel S. Miller, and Z. Valy Vardeny
Organic semiconductors find increasing importance in spin transport devices due to the modulation and control of their properties through chemical synthetic versatility. The organic materials have been used as interlayers between two ferromagnet (FM) electrodes in organic spin valves, as well as for…
[Phys. Rev. B 95, 054423] Published Fri Feb 17, 2017

Domain walls in finite-width nanowires with interfacial Dzyaloshinskii-Moriya interaction

2017-02-17T10:00:00-05:00

Author(s): M. D. DeJong and K. L. Livesey
It is widely known that the interfacial Dzyaloshinskii-Moriya interaction (DMI) may stabilize Néel walls rather than Bloch walls in magnetic thin films. When the DMI is weak, it results in a “tilted” Bloch wall. However, for most applications, domain walls are in nanowires rather than thin films. He…
[Phys. Rev. B 95, 054424] Published Fri Feb 17, 2017

Spin Hall effect and spin swapping in diffusive superconductors

2017-02-17T10:00:00-05:00

Author(s): Camilla Espedal, Peter Lange, Severin Sadjina, A. G. Mal'shukov, and Arne Brataas
We consider the spin-orbit-induced spin Hall effect and spin swapping in diffusive superconductors. By employing the nonequilibrium Keldysh Green's function technique in the quasiclassical approximation, we derive coupled transport equations for the spectral spin and particle distributions and for t…
[Phys. Rev. B 95, 054509] Published Fri Feb 17, 2017

Ba_{8} CoNb_{6} O_{24} : A spin-1/2 triangular-lattice Heisenberg antiferromagnet in the two-dimensional limit

2017-02-17T10:00:00-05:00

Author(s): R. Rawl, L. Ge, H. Agrawal, Y. Kamiya, C. R. Dela Cruz, N. P. Butch, X. F. Sun, M. Lee, E. S. Choi, J. Oitmaa, C. D. Batista, M. Mourigal, H. D. Zhou, and J. Ma
The perovskite Ba_{8}CoNb_{6}O_{24} comprises equilateral effective spin-1/2 Co^{2+} triangular layers separated by six nonmagnetic layers. Susceptibility, specific heat, and neutron scattering measurements combined with high-temperature series expansions and spin-wave calculations confirm that Ba_{…
[Phys. Rev. B 95, 060412(R)] Published Fri Feb 17, 2017

Uniaxial pressure effect on the magnetic ordered moment and transition temperatures in BaFe_{2−x} T_{x} As_{2} (T=Co,Ni)

2017-02-17T10:00:00-05:00

Author(s): David W. Tam, Yu Song, Haoran Man, Sky C. Cheung, Zhiping Yin, Xingye Lu, Weiyi Wang, Benjamin A. Frandsen, Lian Liu, Zizhou Gong, Takashi U. Ito, Yipeng Cai, Murray N. Wilson, Shengli Guo, Keisuke Koshiishi, Wei Tian, Bassam Hitti, Alexandre Ivanov, Yang Zhao, Jeffrey W. Lynn, Graeme M. Luke, Tom Berlijn, Thomas A. Maier, Yasutomo J. Uemura, and Pengcheng Dai
We use neutron diffraction and muon spin relaxation to study the effect of in-plane uniaxial pressure on the antiferromagnetic (AF) orthorhombic phase in BaFe_{2}As_{2} and its Co- and Ni-substituted members near optimal superconductivity. In the low-temperature AF ordered state, uniaxial pressure n…
[Phys. Rev. B 95, 060505(R)] Published Fri Feb 17, 2017

Brittle failure of β- and τ-boron: Amorphization under high pressure

2017-02-17T10:00:00-05:00

Author(s): Qi An and Sergey I. Morozov
Element boron tends to form an icosahedral motif involving 26 electrons, leading to intriguing bonding conditions which complicate understating the structural variations under high pressure. Here we used density function theory (DFT) to examine the mechanical response of β- and recent discovered τ-b…
[Phys. Rev. B 95, 064108] Published Fri Feb 17, 2017

Lattice reconfiguration and phononic band-gap adaptation via origami folding

2017-02-17T10:00:00-05:00

Author(s): M. Thota, S. Li, and K. W. Wang
We introduce a framework of utilizing origami folding to redistribute the inclusions of a phononic structure to achieve significant phononic band-gap adaptation. Cylindrical inclusions are attached to the vertices of a Miura-Ori sheet, whose 1 degree-of-freedom rigid folding can enable fundamental r…
[Phys. Rev. B 95, 064307] Published Fri Feb 17, 2017

Manipulation of magnetic skyrmions with a scanning tunneling microscope

2017-02-17T10:00:00-05:00

Author(s): R. Wieser, R. Shindou, and X. C. Xie
The dynamics of a single magnetic skyrmion in an atomic spin system under the influence of a scanning tunneling microscope is investigated by computer simulations solving the Landau-Lifshitz-Gilbert equation. Two possible scenarios are described: manipulation with aid of a spin-polarized tunneling c…
[Phys. Rev. B 95, 064417] Published Fri Feb 17, 2017

Josephson effect in a Weyl SNS junction

2017-02-17T10:00:00-05:00

Author(s): Kevin A. Madsen, Emil J. Bergholtz, and Piet W. Brouwer
We calculate the Josephson current density j(ϕ) for a Weyl superconductor–normal-metal–superconductor junction for which the outer terminals are superconducting Weyl metals and the normal layer is a Weyl (semi)metal. We describe the Weyl (semi)metal using a simple model with two Weyl points. The mod…
[Phys. Rev. B 95, 064511] Published Fri Feb 17, 2017

Publisher's Note: Modular transformations through sequences of topological charge projections [Phys. Rev. B 94, 165108 (2016)]

2017-02-17T10:00:00-05:00

Author(s): Maissam Barkeshli and Michael Freedman

[Phys. Rev. B 95, 079904] Published Fri Feb 17, 2017

Enhancing chaotic behavior at room temperature in GaAs/(Al,Ga)As superlattices

2017-02-17T10:00:00-05:00

Author(s): M. Ruiz-Garcia, J. Essen, M. Carretero, L. L. Bonilla, and B. Birnir
Previous theoretical and experimental work has put forward 50-period semiconductor superlattices as fast, true random number generators at room temperature. Their randomness stems from feedback between nonlinear electronic dynamics and stochastic processes that are intrinsic to quantum transitions. …
[Phys. Rev. B 95, 085204] Published Fri Feb 17, 2017

Control of the dipole layer of polar organic molecules adsorbed on metal surfaces via different charge-transfer channels

2017-02-17T10:00:00-05:00

Author(s): Meng-Kai Lin, Yasuo Nakayama, Ying-Jie Zhuang, Kai-Jun Su, Chin-Yung Wang, Tun-Wen Pi, Sebastian Metz, Theodoros A. Papadopoulos, T.-C. Chiang, Hisao Ishii, and S.-J. Tang
Organic molecules with a permanent electric dipole moment have been widely used as a template for further growth of molecular layers in device structures. Key properties of the resulting organic films such as energy level alignment (ELA), work function, and injection/collection barrier are linked to…
[Phys. Rev. B 95, 085425] Published Fri Feb 17, 2017

Atomistic calculations of dislocation core energy in aluminium

2017-02-16T10:00:00-05:00

Author(s): X. W. Zhou, R. B. Sills, D. K. Ward, and R. A. Karnesky
A robust molecular-dynamics simulation method for calculating dislocation core energies has been developed. This method has unique advantages: It does not require artificial boundary conditions, is applicable for mixed dislocations, and can yield converged results regardless of the atomistic system …
[Phys. Rev. B 95, 054112] Published Thu Feb 16, 2017

Ultrafast generation of skyrmionic defects with vortex beams: Printing laser profiles on magnets

2017-02-16T10:00:00-05:00

Author(s): Hiroyuki Fujita and Masahiro Sato

Laser beams carrying orbital angular momentum (OAM), first proposed by Allen et al. in 1992, is one of hottest research subjects in modern optics. Such a beam, called an optical vortex, is used to realize superresolution microscopes, chiral optical ablation, optical tweezers, and so on. More recently, electron beams with nonzero OAM are also proposed and experimentally realized. In spite of the growing attention towards such “vortex beams”, their applications for condensed matter physics are almost untapped so far, especially for controlling microscopic electronic and magnetic degrees of freedom in solids. Here, the authors show theoretically that vortex beams can be useful for controlling magnetic properties of solids. In particular, they focus on chiral ferromagnets and antiferromagnets where topologically stable magnetic defects (skyrmions) appear. On the basis of numerical simulations using the stochastic Landau-Lifshitz-Gilbert equation, they show that via the laser-beam-induced spatially nonuniform temperature changes, the characteristic donut-shaped spatial profile of vortex beams can be faithfully transferred to magnets as a family of magnetic defects (n$\pi$ vortices), which include skyrmions and skyrmioniums.

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[Phys. Rev. B 95, 054421] Published Thu Feb 16, 2017

Spin transfer and spin-orbit torques in in-plane magnetized (Ga,Mn)As tracks

2017-02-16T10:00:00-05:00

Author(s): L. Thevenard, B. Boutigny, N. Güsken, L. Becerra, C. Ulysse, S. Shihab, A. Lemaître, J.-V. Kim, V. Jeudy, and C. Gourdon
Current-driven domain wall motion is investigated experimentally in in-plane magnetized (Ga,Mn)As tracks. The wall dynamics is found to differ in two important ways with respect to perpendicularly magnetized (Ga,Mn)As: the wall mobilities are up to ten times higher and the walls move in the same dir…
[Phys. Rev. B 95, 054422] Published Thu Feb 16, 2017

New magnetic phase in the nickelate perovskite TlNiO_{3}

2017-02-16T10:00:00-05:00

Author(s): L. Korosec, M. Pikulski, T. Shiroka, M. Medarde, H. Luetkens, J. A. Alonso, H. R. Ott, and J. Mesot

The rare-earth nickelate perovskites ($R$NiO${}_{3}$, $R$ = rare-earth element) are an archetypal class of correlated electron materials. They order antiferromagnetically at a composition-dependent “Néel” temperature. While it is known that the magnetic structure has a period of four Ni spins along each (pseudo)cubic crystal axis, the arrangement of these spins is still under debate, especially in view of the conjecture of ferroelectricity in the antiferromagnetic phase. Here, the authors report the experimental discovery of an unexpected second magnetic phase transition in TlNiO${}_{3}$, a material closely resembling the analogous rare-earth compounds. Results of nuclear magnetic resonance and muon spin rotation experiments reveal the presence of two distinct magnetic phase transitions. The new phase is suppressed by magnetic fields on the order of at most 1 T.

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[Phys. Rev. B 95, 060411(R)] Published Thu Feb 16, 2017

Dislocations near elastic instability in high-pressure body-centered-cubic magnesium

2017-02-16T10:00:00-05:00

Author(s): I. S. Winter, M. Poschmann, T. Tsuru, and D. C. Chrzan
At high pressure, Mg is expected to transform to the body-centered-cubic (BCC) phase. We use density functional theory to explore the structure of 〈111〉-type dislocation cores in BCC Mg as a function of pressure. As the pressure is reduced from the region of absolute stability for the BCC phase, the…
[Phys. Rev. B 95, 064107] Published Thu Feb 16, 2017

Modeling the thickness dependence of the magnetic phase transition temperature in thin FeRh films

2017-02-16T10:00:00-05:00

Author(s): Thomas Andrew Ostler, Craig Barton, Thomas Thomson, and Gino Hrkac
FeRh and its first-order phase transition can open new routes for magnetic hybrid materials and devices under the assumption that it can be exploited in ultra-thin-film structures. Motivated by experimental measurements showing an unexpected increase in the phase transition temperature with decreasi…
[Phys. Rev. B 95, 064415] Published Thu Feb 16, 2017

Calculated g-factors of 5d double perovskites Ba_{2} NaOsO_{6} and Ba_{2} YOsO_{6}

2017-02-16T10:00:00-05:00

Author(s): Kyo-Hoon Ahn, Karel Pajskr, Kwan-Woo Lee, and Jan Kuneš
Using Wannier functions to represent the density functional results we calculate the hybridization corrections to the orbital momentum operator in the Os 5d shell of the Mott insulators Ba_{2}NaOsO_{6} and Ba_{2}YOsO_{6}. The g-factors are obtained by evaluating the spin and orbital momentum operato…
[Phys. Rev. B 95, 064416] Published Thu Feb 16, 2017

Self-consistent study of Abelian and non-Abelian order in a two-dimensional topological superconductor

2017-02-16T10:00:00-05:00

Author(s): S. L. Goertzen, K. Tanaka, and Yuki Nagai
We perform self-consistent studies of two-dimensional (2D) s-wave topological superconductivity (TSC) with Rashba spin-orbit coupling and Zeeman field by solving the Bogoliubov-de Gennes equations. In particular, we examine the effects of a nonmagnetic impurity in detail and show that the nature of …
[Phys. Rev. B 95, 064509] Published Thu Feb 16, 2017

Shapes of rotating superfluid helium nanodroplets

2017-02-16T10:00:00-05:00

Author(s): Charles Bernando, Rico Mayro P. Tanyag, Curtis Jones, Camila Bacellar, Maximilian Bucher, Ken R. Ferguson, Daniela Rupp, Michael P. Ziemkiewicz, Luis F. Gomez, Adam S. Chatterley, Tais Gorkhover, Maria Müller, John Bozek, Sebastian Carron, Justin Kwok, Samuel L. Butler, Thomas Möller, Christoph Bostedt, Oliver Gessner, and Andrey F. Vilesov

Helium nanodroplets are considered ideal model systems to explore quantum hydrodynamics in self-contained, isolated superfluids. Rotation of a superfluid droplet is manifested as a collection of quantum vortices. Here, the authors use single-shot femtosecond X-ray coherent diffractive imaging to investigate the shapes and vorticity of rotating superfluid ${}^{4}$He droplets. They find that most of the diffraction contours exhibit noticeable ellipticity. A smaller but still significant number of distorted diffraction contours are marked by regions of high intensity concentrated along the direction of the long axis in the diffraction image, indicating the presence of extremely deformed ${}^{4}$He droplets. Forward modeling of the diffraction images shows that the shapes of superfluid ${}^{4}$He droplets are very similar to their classical counterparts. In particular, the existence of both axially symmetric (oblate) and, for higher angular momenta, two-lobed (triaxial prolate) droplets is revealed. The latter shapes are strongly deformed compared to the spheroidal bodies that are expected for smaller rotational speeds. The observed shapes provide direct access to the droplet angular momenta, angular velocities, and estimated number of quantum vortices inside the droplets.

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[Phys. Rev. B 95, 064510] Published Thu Feb 16, 2017

Theory of quantum kagome ice and vison zero modes

2017-02-16T10:00:00-05:00

Author(s): Yi-Ping Huang and Michael Hermele
We derive an effective Z_{2} gauge theory to describe the quantum kagome ice (QKI) state that has been observed by Carrasquilla et al. [Nat. Commun. 6, 7421 (2015)] in Monte Carlo studies of the S=1/2 kagome XYZ model in a Zeeman field. The numerical results on QKI are consistent with, but do not co…
[Phys. Rev. B 95, 075130] Published Thu Feb 16, 2017

Superuniversality of topological quantum phase transition and global phase diagram of dirty topological systems in three dimensions

2017-02-16T10:00:00-05:00

Author(s): Pallab Goswami and Sudip Chakravarty
The quantum phase transition between two clean, noninteracting topologically distinct gapped states in three dimensions is governed by a massless Dirac fermion fixed point, irrespective of the underlying symmetry class, and this constitutes a remarkably simple example of superuniversality. For a suf…
[Phys. Rev. B 95, 075131] Published Thu Feb 16, 2017

First-principles mode-by-mode analysis for electron-phonon scattering channels and mean free path spectra in GaAs

2017-02-16T10:00:00-05:00

Author(s): Te-Huan Liu, Jiawei Zhou, Bolin Liao, David J. Singh, and Gang Chen
We present a first-principles framework to investigate the electron scattering channels and transport properties for polar materials by combining the exact solution of the linearized electron-phonon (e-ph) Boltzmann transport equation in its integral-differential form associated with the e-ph coupli…
[Phys. Rev. B 95, 075206] Published Thu Feb 16, 2017

Chern insulators without band inversion in MoS_{2} monolayers with 3d adatoms

2017-02-16T10:00:00-05:00

Author(s): Xinyuan Wei, Bao Zhao, Jiayong Zhang, Yang Xue, Yun Li, and Zhongqin Yang
Electronic and topological properties of MoS_{2} monolayers endowed with 3d transition metal (TM) adatoms (V-Fe) are explored by using ab initio methods and k·p models. Without the consideration of the Hubbard U interaction, the V, Cr, and Fe adatoms tend to locate on the top of the Mo atoms, while …
[Phys. Rev. B 95, 075419] Published Thu Feb 16, 2017

On the nature of the Mott transition in multiorbital systems

2017-02-16T10:00:00-05:00

Author(s): Jorge I. Facio, V. Vildosola, D. J. García, and Pablo S. Cornaglia
We analyze the nature of a Mott metal-insulator transition in multiorbital systems using dynamical mean-field theory. The auxiliary multiorbital quantum impurity problem is solved using continuous-time quantum Monte Carlo and the rotationally invariant slave-boson (RISB) mean-field approximation. We…
[Phys. Rev. B 95, 085119] Published Thu Feb 16, 2017

Competing orders and topology in the global phase diagram of pyrochlore iridates

2017-02-16T10:00:00-05:00

Author(s): Pallab Goswami, Bitan Roy, and Sankar Das Sarma
Strong electronic interactions and spin-orbit coupling can be conducive for realizing novel broken symmetry phases supporting quasiparticles with nontrivial band topology. 227 pyrochlore iridates provide a suitable material platform for studying such emergent phenomena where both topology and compet…
[Phys. Rev. B 95, 085120] Published Thu Feb 16, 2017

Non-Fermi-liquid behavior in quantum impurity models with superconducting channels

2017-02-16T10:00:00-05:00

Author(s): Rok Žitko and Michele Fabrizio
We study how the non-Fermi-liquid nature of the overscreened multichannel Kondo impurity model affects the response to a BCS pairing term that, in the absence of the impurity, opens a gap Δ. We find that the low-energy spectrum in the limit Δ→0 actually does not correspond to the spectrum strictly a…
[Phys. Rev. B 95, 085121] Published Thu Feb 16, 2017

Vibrational effects in charge transport through a molecular double quantum dot

2017-02-16T10:00:00-05:00

Author(s): Jakub K. Sowa, Jan A. Mol, G. Andrew D. Briggs, and Erik M. Gauger
Recent progress in the field of molecular electronics has revealed the fundamental importance of the coupling between the electronic degrees of freedom and specific vibrational modes. Considering the examples of a molecular dimer and a carbon nanotube double quantum dot, we here theoretically invest…
[Phys. Rev. B 95, 085423] Published Thu Feb 16, 2017

Accuracy of first-principles interatomic interactions and predictions of ferroelectric phase transitions in perovskite oxides: Energy functional and effective Hamiltonian

2017-02-15T10:00:00-05:00

Author(s): Arpita Paul, Jianwei Sun, John P. Perdew, and Umesh V. Waghmare
While first-principles density functional theory (DFT)-based models have been effective in capturing the physics of ferroelectric phase transitions in BaTiO_{3}, PbTiO_{3}, and KNbO_{3}, quantitative estimates of the transition temperatures (T_{C}) suffer from errors that are believed to originate f…
[Phys. Rev. B 95, 054111] Published Wed Feb 15, 2017

Topology of a dissipative spin: Dynamical Chern number, bath-induced nonadiabaticity, and a quantum dynamo effect

2017-02-15T10:00:00-05:00

Author(s): Loïc Henriet, Antonio Sclocchi, Peter P. Orth, and Karyn Le Hur
We analyze the topological deformations of the ground state manifold of a quantum spin-1/2 in a magnetic field H=H(sinθcosϕ,sinθsinϕ,cosθ) induced by a coupling to an ohmic quantum dissipative environment at zero temperature. From Bethe ansatz results and a variational approach, we confirm that the …
[Phys. Rev. B 95, 054307] Published Wed Feb 15, 2017

NMR investigation of spin fluctuations in the itinerant-electron magnetic compound Sr_{1−x} Ca_{x} Co_{2} P_{2}

2017-02-15T10:00:00-05:00

Author(s): Masaki Imai, Chishiro Michioka, Hiroaki Ueda, and Kazuyoshi Yoshimura
We took ^{31}P NMR measurements of mainly paramagnetic phase Sr_{1−x}Ca_{x}Co_{2}P_{2} (0≤x≤0.5) to reveal the itinerant-electron metamagnetic transition, and of its magnetically ordered phase (0.7≤x≤1), and characterized their spin fluctuations by estimating the spin fluctuation parameter T_{0} cor…
[Phys. Rev. B 95, 054417] Published Wed Feb 15, 2017

Functional renormalization group analysis of Dzyaloshinsky-Moriya and Heisenberg spin interactions on the kagome lattice

2017-02-15T10:00:00-05:00

Author(s): Max Hering and Johannes Reuther
We investigate the effects of Dzyaloshinsky-Moriya (DM) interactions on the frustrated J_{1}−J_{2} kagome-Heisenberg model using the pseudofermion functional renormalization group (PFFRG) technique. In order to treat the off-diagonal nature of DM interactions, we develop an extended PFFRG scheme. We…
[Phys. Rev. B 95, 054418] Published Wed Feb 15, 2017

Impurities near an antiferromagnetic-singlet quantum critical point

2017-02-15T10:00:00-05:00

Author(s): T. Mendes-Santos, N. C. Costa, G. Batrouni, N. Curro, R. R. dos Santos, T. Paiva, and R. T. Scalettar
Heavy-fermion systems and other strongly correlated electron materials often exhibit a competition between antiferromagnetic (AF) and singlet ground states. Using exact quantum Monte Carlo simulations, we examine the effect of impurities in the vicinity of such an AF-singlet quantum critical point (…
[Phys. Rev. B 95, 054419] Published Wed Feb 15, 2017

Temperature-induced phase transition from cycloidal to collinear antiferromagnetism in multiferroic Bi_{0.9} Sm_{0.1} FeO_{3} driven by f−d induced magnetic anisotropy

2017-02-15T10:00:00-05:00

Author(s): R. D. Johnson, P. A. McClarty, D. D. Khalyavin, P. Manuel, P. Svedlindh, and C. S. Knee
In multiferroic BiFeO_{3} a cycloidal antiferromagnetic structure is coupled to a large electric polarization at room temperature, giving rise to magnetoelectric functionality that may be exploited in novel multiferroic-based devices. In this paper, we demonstrate that substituting samarium for 10% …
[Phys. Rev. B 95, 054420] Published Wed Feb 15, 2017

Superconductivity in two-dimensional disordered Dirac semimetals

2017-02-15T10:00:00-05:00

Author(s): Jing Wang, Peng-Lu Zhao, Jing-Rong Wang, and Guo-Zhu Liu
In two-dimensional Dirac semimetals, Cooper pairing instability occurs only when the attractive interaction strength |u| is larger than some critical value |u_{c}| because the density of states vanishes at Dirac points. Disorders enhance the low-energy density of states but meanwhile shorten the lif…
[Phys. Rev. B 95, 054507] Published Wed Feb 15, 2017

Cu nuclear magnetic resonance study of charge and spin stripe order in La_{1.875} Ba_{0.125} CuO_{4}

2017-02-15T10:00:00-05:00

Author(s): D. Pelc, H.-J. Grafe, G. D. Gu, and M. Požek
We present a Cu nuclear magnetic/quadrupole resonance study of the charge stripe ordered phase of LBCO, with detection of previously unobserved (“wiped-out”) signal. We show that spin-spin and spin-lattice relaxation rates are strongly enhanced in the charge ordered phase, explaining the apparent si…
[Phys. Rev. B 95, 054508] Published Wed Feb 15, 2017

Charge partitioning and anomalous hole doping in Rh-doped Sr_{2} IrO_{4}

2017-02-15T10:00:00-05:00

Author(s): S. Chikara, G. Fabbris, J. Terzic, G. Cao, D. Khomskii, and D. Haskel

The simultaneous presence of sizable spin-orbit interactions and electron correlations in iridates has led to predictions of novel electronic ground states, including Dirac semimetals, Kitaev spin liquids, and superconductivity. Electron and hole-doping studies of Sr${}_{2}$IrO${}_{4}$ are one of the venues being pursued to attain such novel quantum states, driven in part by the extensive parallels with the La${}_{2}$CuO${}_{4}$ parent compound of high-${T}_{c}$ cuprates. In particular, Rh doping has been intensively pursued but the mechanism of electronic doping and its impact on the evolution of magnetic and transport properties has been under scrutiny. Using x-ray absorption spectroscopy at the Rh $K$, $L$, and Ir $L$ edges, the authors reveal unusual charge partitioning between Rh and Ir sites. The resultant anomalous doping introduces holes into the ${J}_{\text{eff}}$=1/2 band at low Rh content only for these holes to be removed at higher Rh content. This anomalous doping provides a natural explanation for the reentrant insulating phase in the phase diagram of Rh-doped Sr${}_{2}$IrO${}_{4}$ and should be taken into account when searching for novel electronic phases in 5$d$ iridates doped with 4$d$ or 3$d$ elements where anomalous charge partitioning is expected.

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[Phys. Rev. B 95, 060407(R)] Published Wed Feb 15, 2017

Strength of effective Coulomb interactions and origin of ferromagnetism in hydrogenated graphene

2017-02-15T10:00:00-05:00

Author(s): E. Şaşıoğlu, H. Hadipour, C. Friedrich, S. Blügel, and I. Mertig
Hydrogenation provides a novel way to tune the electronic properties of graphene. Recent scanning tunneling microscopy experiments have demonstrated that local graphene magnetism can be selectively switched on and off by hydrogen (H) dimers. Employing first-principles calculations in conjunction wit…
[Phys. Rev. B 95, 060408(R)] Published Wed Feb 15, 2017

Parametric frequency mixing in a magnetoelastically driven linear ferromagnetic-resonance oscillator

2017-02-15T10:00:00-05:00

Author(s): C. L. Chang, A. M. Lomonosov, J. Janusonis, V. S. Vlasov, V. V. Temnov, and R. I. Tobey
We demonstrate the linear frequency conversion of ferromagnetic resonance (FMR) frequency by optically excited elastic waves in a thin metallic film on dielectric substrates. Time-resolved probing of the magnetization directly witnesses magnetoelastically driven parametric second-harmonic generation…
[Phys. Rev. B 95, 060409(R)] Published Wed Feb 15, 2017

Completely compensated ferrimagnetism and sublattice spin crossing in the half-metallic Heusler compound Mn_{1.5} FeV_{0.5} Al

2017-02-15T10:00:00-05:00

Author(s): Rolf Stinshoff, Ajaya K. Nayak, Gerhard H. Fecher, Benjamin Balke, Siham Ouardi, Yurii Skourski, Tetsuya Nakamura, and Claudia Felser
The Slater-Pauling rule states that L2_{1} Heusler compounds with 24 valence electrons never exhibit a total spin magnetic moment. In the case of strongly localized magnetic moments at one of the atoms (here Mn) they will exhibit a fully compensated half-metallic ferrimagnetic state instead, in part…
[Phys. Rev. B 95, 060410(R)] Published Wed Feb 15, 2017

Reversible structural transition in nanoconfined ice

2017-02-15T10:00:00-05:00

Author(s): V. Satarifard, M. Mousaei, F. Hadadi, James Dix, M. Sobrino Fernandez, P. Carbone, J. Beheshtian, F. M. Peeters, and M. Neek-Amal
The report on square ice sandwiched between two graphene layers by Algara-Siller et al. [Nature (London) 519, 443 (2015)] has generated a large interest in this system. By applying high lateral pressure on nanoconfined water, we found that monolayer ice is transformed to bilayer ice when the two gra…
[Phys. Rev. B 95, 064105] Published Wed Feb 15, 2017

Using capillary forces to determine the elastic properties of mesoporous materials

2017-02-15T10:00:00-05:00

Author(s): E. Rolley, N. Garroum, and A. Grosman
The capillary forces in mesoporous materials, when imbibed with liquid, are large enough to induce mechanical deformations. Using anisotropic porous silicon, we show that systematic measurements of strain as a function of the pore pressure can yield most of the elastic constants characterizing the p…
[Phys. Rev. B 95, 064106] Published Wed Feb 15, 2017

Mode mixing induced by disorder in a graphene pnp junction in a magnetic field

2017-02-15T10:00:00-05:00

Author(s): Ning Dai and Qing-Feng Sun
We study the electron transport through the graphene pnp junction under a magnetic field and show that mode mixing plays an essential role. By using the nonequilibrium Green's function method, the space distribution of the scattering state for a specific incident mode as well the elements of the tra…
[Phys. Rev. B 95, 064205] Published Wed Feb 15, 2017

Broadband ferromagnetic resonance characterization of anisotropies and relaxation in exchange-biased IrMn/CoFe bilayers

2017-02-15T10:00:00-05:00

Author(s): Jamileh Beik Mohammadi, Joshua Michael Jones, Soumalya Paul, Behrouz Khodadadi, Claudia K. A. Mewes, Tim Mewes, and Christian Kaiser
The magnetization dynamics of exchange-biased IrMn/CoFe bilayers have been investigated using broadband and in-plane angle-dependent ferromagnetic resonance spectroscopy. The interface energy of the exchange bias effect in these bilayers exceeds values previously reported for metallic antiferromagne…
[Phys. Rev. B 95, 064414] Published Wed Feb 15, 2017

Observation of the magnetic C_{4} phase in Ca_{1−x} Na_{x} Fe_{2} As_{2} and its universality in the hole-doped 122 superconductors

2017-02-15T10:00:00-05:00

Author(s): K. M. Taddei, J. M. Allred, D. E. Bugaris, S. H. Lapidus, M. J. Krogstad, H. Claus, D. Y. Chung, M. G. Kanatzidis, R. Osborn, S. Rosenkranz, and O. Chmaissem
Since its discovery in 2014, the magnetic tetragonal C_{4} phase has been identified in a growing number of hole-doped 122 Fe-based superconducting compounds. Exhibiting a unique double-Q magnetic structure and a strong competition with both superconducting and magnetic order parameters, the C_{4} p…
[Phys. Rev. B 95, 064508] Published Wed Feb 15, 2017

Insulating phases of vanadium dioxide are Mott-Hubbard insulators

2017-02-15T10:00:00-05:00

Author(s): T. J. Huffman, C. Hendriks, E. J. Walter, Joonseok Yoon, Honglyoul Ju, R. Smith, G. L. Carr, H. Krakauer, and M. M. Qazilbash
We present comprehensive broadband optical spectroscopy data on two insulating phases of vanadium dioxide (VO_{2}): monoclinic M_{2} and triclinic. The main result of our work is that the energy gap and the electronic structure are essentially unaltered by the first-order structural phase transition…
[Phys. Rev. B 95, 075125] Published Wed Feb 15, 2017

Spin-phonon coupling in epitaxial Sr_{0.6} Ba_{0.4} MnO_{3} thin films

2017-02-15T10:00:00-05:00

Author(s): V. Goian, E. Langenberg, N. Marcano, V. Bovtun, L. Maurel, M. Kempa, T. Prokscha, J. Kroupa, P. A. Algarabel, J. A. Pardo, and S. Kamba
Spin-phonon coupling is investigated in epitaxially strained Sr_{1−x}Ba_{x}MnO_{3} thin films with perovskite structure by means of microwave (MW) and infrared (IR) spectroscopy. In this work we focus on the Sr_{0.6}Ba_{0.4}MnO_{3} composition grown on (LaAlO_{3})_{0.3}(Sr_{2}AlTaO_{6})_{0.7} substr…
[Phys. Rev. B 95, 075126] Published Wed Feb 15, 2017

Shear viscosity at the Ising-nematic quantum critical point in two-dimensional metals

2017-02-15T10:00:00-05:00

Author(s): Andreas Eberlein, Aavishkar A. Patel, and Subir Sachdev
In an isotropic strongly interacting quantum liquid without quasiparticles, general scaling arguments imply that the dimensionless ratio (k_{B}/ℏ)η/s, where η is the shear viscosity and s is the entropy density, is a universal number. We compute the shear viscosity of the Ising-nematic critical poin…
[Phys. Rev. B 95, 075127] Published Wed Feb 15, 2017

Strong anisotropic anomalous Hall effect and spin Hall effect in the chiral antiferromagnetic compounds Mn_{3} X (X=Ge, Sn, Ga, Ir, Rh, and Pt)

2017-02-15T10:00:00-05:00

Author(s): Yang Zhang, Yan Sun, Hao Yang, Jakub Železný, Stuart P. P. Parkin, Claudia Felser, and Binghai Yan
We have carried out a comprehensive study of the intrinsic anomalous Hall effect and spin Hall effect of several chiral antiferromagnetic compounds Mn_{3}X (X = Ge, Sn, Ga, Ir, Rh and Pt) by ab initio band structure and Berry phase calculations. These studies reveal large and anisotropic values of b…
[Phys. Rev. B 95, 075128] Published Wed Feb 15, 2017

Excitonic pairing and insulating transition in two-dimensional semi-Dirac semimetals

2017-02-15T10:00:00-05:00

Author(s): Jing-Rong Wang, Guo-Zhu Liu, and Chang-Jin Zhang
A sufficiently strong long-range Coulomb interaction can induce excitonic pairing in gapless Dirac semimetals, which generates a finite gap and drives the semimetal-insulator quantum phase transition. This phenomenon is in close analogy to dynamical chiral symmetry breaking in high-energy physics. I…
[Phys. Rev. B 95, 075129] Published Wed Feb 15, 2017

Effect of intervalley interaction on band topology of commensurate graphene/EuO heterostructures

2017-02-15T10:00:00-05:00

Author(s): Shanshan Su, Yafis Barlas, Junxue Li, Jing Shi, and Roger K. Lake
Recent experiments demonstrating proximity induced ferromagnetism in graphene motivate this study of commensurate graphene/EuO heterostructures. Due to the commensurability of graphene with the (111)-EuO layer, graphene's Dirac points are mapped to the Γ point of the commensurate Brillouin zone. The…
[Phys. Rev. B 95, 075418] Published Wed Feb 15, 2017

Erratum: Dynamics of nonequilibrium electrons on neutral center states of interstitial magnesium donors in silicon [Phys. Rev. B 94, 075208 (2016)]

2017-02-15T10:00:00-05:00

Author(s): S. G. Pavlov, N. Deßmann, A. Pohl, V. B. Shuman, L. М. Portsel, А. N. Lodygin, Yu. A. Astrov, S. Winnerl, H. Schneider, N. Stavrias, A. F. G. van der Meer, V. V. Tsyplenkov, K. A. Kovalevsky, R. Kh. Zhukavin, V. N. Shastin, N. V. Abrosimov, and H.-W. Hübers
[Phys. Rev. B 95, 079903] Published Wed Feb 15, 2017

Rehabilitation of the Perdew-Burke-Ernzerhof generalized gradient approximation for layered materials

2017-02-15T10:00:00-05:00

Author(s): Haowei Peng and John P. Perdew
The structural and energetic properties of layered materials present a challenge to density functional theory with common semilocal approximations to the exchange-correlation energy. By combining the most widely used semilocal generalized gradient approximation (GGA), the Perdew-Burke-Ernzerhof (PBE…
[Phys. Rev. B 95, 081105(R)] Published Wed Feb 15, 2017

Revealing the spin optics in conic-shaped metasurfaces

2017-02-15T10:00:00-05:00

Author(s): Yanjun Bao, Shuai Zu, Wei Liu, Lei Zhou, Xing Zhu, and Zheyu Fang
Ellipse and hyperbola are two well-known curves in mathematics with numerous applications in various fields, but their properties and inherent differences in spin optics are less understood. Here, we investigate the peculiar optical spin properties of the two curves and establish a connection betwee…
[Phys. Rev. B 95, 081406(R)] Published Wed Feb 15, 2017

BaSn_{2} : A wide-gap strong topological insulator

2017-02-15T10:00:00-05:00

Author(s): Steve M. Young, S. Manni, Junping Shao, Paul C. Canfield, and Aleksey N. Kolmogorov
BaSn_{2} has been shown to form as layers of buckled stanene intercalated by barium ions. However, despite an apparently straightforward synthesis and significant interest in stanene as a topological material, BaSn_{2} has been left largely unexplored, and has only recently been recognized as a pote…
[Phys. Rev. B 95, 085116] Published Wed Feb 15, 2017

Electronic band structure for occupied and unoccupied states of the natural topological superlattice phase Sb_{2} Te

2017-02-15T10:00:00-05:00

Author(s): L. Khalil, E. Papalazarou, M. Caputo, N. Nilforoushan, L. Perfetti, A. Taleb-Ibrahimi, V. Kandyba, A. Barinov, Q. D. Gibson, R. J. Cava, and M. Marsi
We present an experimental study describing the effects of surface termination on the electronic structure of the natural topological superlattice phase Sb_{2}Te. Using scanning angle-resolved photoemission microscopy, we consistently find various nonequivalent regions on the same surface after clea…
[Phys. Rev. B 95, 085118] Published Wed Feb 15, 2017

Entangled light from bimodal optical nanoantennas

2017-02-15T10:00:00-05:00

Author(s): J. Straubel, R. Sarniak, C. Rockstuhl, and K. Słowik
We suggest a hybrid plasmonic device made of a bimodal metallic nanoantenna coupled to an incoherently pumped quantum emitter. This device emits light into the two modes entangled in the number of photons. The process is a prime example of losses changing from being a nuisance into something benefic…
[Phys. Rev. B 95, 085421] Published Wed Feb 15, 2017

Alternative structure of TiO_{2} with higher energy valence band edge

2017-02-15T10:00:00-05:00

Author(s): Sinisa Coh, Peter Y. Yu, Yuta Aoki, Susumu Saito, Steven G. Louie, and Marvin L. Cohen
We propose an alternative structure of TiO_{2} anatase that has a higher energy oxygen p-like valence band maximum than pristine TiO_{2} anatase and thus has a much better alignment with the water splitting levels. This alternative structure is unique when considering a large subspace of possible st…
[Phys. Rev. B 95, 085422] Published Wed Feb 15, 2017

Unveiling descriptors for predicting the bulk modulus of amorphous carbon

2017-02-14T10:00:00-05:00

Author(s): Keisuke Takahashi and Yuzuru Tanaka
Descriptors for the bulk modulus of amorphous carbon are investigated through the implementation of data mining where data sets are prepared using first-principles calculations. Data mining reveals that the number of bonds in each C atom and the density of amorphous carbon are found to be descriptor…
[Phys. Rev. B 95, 054110] Published Tue Feb 14, 2017

Relaxation mechanism in NiFe thin films driven by spin angular momentum absorption throughout the antiferromagnetic phase transition in native surface oxides

2017-02-14T10:00:00-05:00

Author(s): L. Frangou, G. Forestier, S. Auffret, S. Gambarelli, and V. Baltz
We report an alternative mechanism for the physical origin of the temperature-dependent ferromagnetic relaxation observed in bare permalloy (NiFe) thin films. Through spin-pumping experiments, we demonstrate that the peak in the temperature dependence of NiFe damping can be understood in terms of en…
[Phys. Rev. B 95, 054416] Published Tue Feb 14, 2017

Anisotropic superconducting gaps in YNi_{2} B_{2} C: A first-principles investigation

2017-02-14T10:00:00-05:00

Author(s): Mitsuaki Kawamura, Ryosuke Akashi, and Shinji Tsuneyuki
We calculate superconducting gaps and quasiparticle density of states of YNi_{2}B_{2}C in the framework of the density functional theory for superconductors to investigate the origin of highly anisotropic superconducting gaps in this material. Calculated phonon frequencies, the quasiparticle density…
[Phys. Rev. B 95, 054506] Published Tue Feb 14, 2017

Infrared spectroscopic study on lattice dynamics in CaFeO_{3}

2017-02-14T10:00:00-05:00

Author(s): C. X. Zhang, H. L. Xia, H. Liu, Y. M. Dai, B. Xu, R. Yang, Z. Y. Qiu, Q. T. Sui, Y. W. Long, S. Meng, and X. G. Qiu
The change of the lattice dynamics upon the charge disproportionation (CD) transition has been investigated for the CaFeO_{3} crystal by measuring its infrared optical spectra. Across the CD transition, CaFeO_{3} undergoes a metal-insulator transition, and it is found that below T_{CD}≈290 K the low…
[Phys. Rev. B 95, 064104] Published Tue Feb 14, 2017

Acoustic solitons: A robust tool to investigate the generation and detection of ultrafast acoustic waves

2017-02-14T10:00:00-05:00

Author(s): Emmanuel Péronne, Nicolas Chuecos, Laura Thevenard, and Bernard Perrin

Solitons are self-preserving traveling waves of great interest in nonlinear physics, offering many interesting application such as high-bandwidth optical fiber communication. Solitons can also appear in ultrafast acoustics, and several observations suggest acoustic solitons as short as 200 fs. Here, the authors designed an experimental setup to observe and characterize acoustic solitons traveling through a GaAs(001) substrate. The experimental signal is explained well with the help of the Korteweg–de Vries equation, demonstrating the particlelike nature and the unique properties of the solitons. Moreover, the temporal distribution of the solitons is also analyzed with the help of the inverse scattering method. Such investigations provide a new tool to probe transient properties of highly excited matter through the study of the solitons due to the acoustic pulse emitted after laser excitation.

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[Phys. Rev. B 95, 064306] Published Tue Feb 14, 2017

Spin Hall torques generated by rare-earth thin films

2017-02-14T10:00:00-05:00

Author(s): Neal Reynolds, Priyamvada Jadaun, John T. Heron, Colin L. Jermain, Jonathan Gibbons, Robyn Collette, R. A. Buhrman, D. G. Schlom, and D. C. Ralph

The spin Hall effect is of great technological interest because it can produce efficient spin-transfer torques with the potential to advance magnetic memory technologies. Here, the authors demonstrate that the spin Hall effect can be enhanced by the presence of $f$-orbital states near the Fermi level. The authors compare measurements of spin Hall torques generated by the rare-earth metals Gd, Dy, Ho, and Lu with the results of first-principles calculations of intrinsic spin Hall conductivity with and without $f$-orbital participation. They find that contributions from the $f$-orbital states are required to explain the experimental trend in spin Hall conductivity as a function of $f$-orbital filling. The observed trend is consistent in both sign and magnitude with a simple Hund’s rules picture of $f$-orbital filling, similar to the trend observed in the 4$d$ and 5$d$ transition metals as a function of $d$-orbital filling. These results suggest that rare earths are a promising research direction for creating and tailoring materials with large spin-orbit torques.

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[Phys. Rev. B 95, 064412] Published Tue Feb 14, 2017

Optical hyperpolarization of nitrogen donor spins in bulk diamond

2017-02-14T10:00:00-05:00

Author(s): M. Loretz, H. Takahashi, T. F. Segawa, J. M. Boss, and C. L. Degen
We report hyperpolarization of the electronic spins associated with substitutional nitrogen defects in bulk diamond crystals. Hyperpolarization is achieved by optical pumping of nitrogen vacancy centers followed by rapid cross relaxation at the energy level matching condition in a 51 mT bias field. …
[Phys. Rev. B 95, 064413] Published Tue Feb 14, 2017

Geometric structure of anatase TiO_{2} (101)

2017-02-14T10:00:00-05:00

Author(s): Jon P. W. Treacy, Hadeel Hussain, Xavier Torrelles, David C. Grinter, Gregory Cabailh, Oier Bikondoa, Christopher Nicklin, Sencer Selcuk, Annabella Selloni, Robert Lindsay, and Geoff Thornton
Surface x-ray diffraction has been used to determine the quantitative structure of the (101) termination of anatase TiO_{2}. The atomic displacements from the bulk-terminated structure are significantly different from those previously calculated with density functional theory (DFT) methods with disc…
[Phys. Rev. B 95, 075416] Published Tue Feb 14, 2017

Topological transconductance quantization in a four-terminal Josephson junction

2017-02-14T10:00:00-05:00

Author(s): Erik Eriksson, Roman-Pascal Riwar, Manuel Houzet, Julia S. Meyer, and Yuli V. Nazarov

The investigation of topological transitions in quantum systems is a thriving area of modern research. The authors recently predicted that multiterminal Josephson junctions realize a novel type of topological matter. Weyl singularities may appear in the Andreev bound-state spectrum of junctions with four superconducting terminals, giving rise to topological transitions as the superconducting phases are tuned. These transitions manifest themselves in a quantization of the transconductance between two voltage-biased terminals in fundamental units of 4${e}^{2}$2/$h$, where $e$ is the electric charge and $h$ is the Planck constant. The present work addresses the observability of this effect. The quantized transconductance is associated with adiabatic transport at fixed occupations of the Andreev states. On the other hand, a bias voltage leads to multiple Andreev reflections, where a quasiparticle is dissipatively transferred from the occupied states below the superconducting gap to the empty states above the superconducting gap. By computing the currents in the presence of weak inelastic relaxation, the authors establish the voltage threshold below which the equilibrium occupations of the Andreev states are restored, and the transconductances reach their quantized values. The results are an important step towards experimental verification of the topological properties of multiterminal Josephson junctions.

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[Phys. Rev. B 95, 075417] Published Tue Feb 14, 2017

Fermi arcs formation in Weyl semimetals: The key role of intervalley interaction

2017-02-14T10:00:00-05:00

Author(s): Zh. A. Devizorova and V. A. Volkov
We propose an analytical model describing Fermi arc surface states observed in the recent investigations of Weyl semimetals. The effective two-valley Hamiltonian is supplemented by the boundary conditions taking into account both the intravalley and intervalley interfacial interactions. We demonstra…
[Phys. Rev. B 95, 081302(R)] Published Tue Feb 14, 2017

Nonlocal magnetoresistance measurements of the organic zero-gap conductor α−(BEDT−TTF)_{2} I_{3}

2017-02-14T10:00:00-05:00

Author(s): Takeshi Kamiya, Yoshitaka Kawasugi, Masato Ara, and Hirokazu Tada
We prepared nonlocal spin valves based on single crystals of an organic multilayered zero-gap conductor α−(BEDT−TTF)_{2}I_{3} and succeeded in evaluating the spin-diffusion length (1.1 μm) and relaxation time (3 ns) at 2.5 K under a static pressure of 1.6 GPa using a polyethylene naphthalate as a su…
[Phys. Rev. B 95, 085307] Published Tue Feb 14, 2017

Band-unfolding approach to moiré-induced band-gap opening and Fermi level velocity reduction in twisted bilayer graphene

2017-02-14T10:00:00-05:00

Author(s): Hirofumi Nishi, Yu-ichiro Matsushita, and Atsushi Oshiyama
We report on the energy spectrum of electrons in twisted bilayer graphene (tBLG) obtained by the band-unfolding method in the tight-binding model. We find the band-gap opening at particular points in the reciprocal space, that elucidates the drastic reduction of the Fermi-level velocity with the tin…
[Phys. Rev. B 95, 085420] Published Tue Feb 14, 2017

Interfacial free energy and medium range order: Proof of an inverse of Frank's hypothesis

2017-02-13T10:00:00-05:00

Author(s): Geun Woo Lee, Yong Chan Cho, Byeongchan Lee, and Kenneth F. Kelton
We study the relation of crystal-liquid interfacial free energy and medium range order in the quasicrystal-forming Ti_{37}Zr_{42}Ni_{21} liquid from undercooling experiment and ab initio molecular dynamics (MD) simulation. Adding a small amount of Ag to the liquid significantly reduces the degree of…
[Phys. Rev. B 95, 054202] Published Mon Feb 13, 2017

Theory of harmonic dissipation in disordered solids

2017-02-13T10:00:00-05:00

Author(s): T. Damart, A. Tanguy, and D. Rodney
Mechanical spectroscopy, i.e., cyclic deformations at varying frequencies, is used theoretically and numerically to compute dissipation in model glasses. From a normal mode analysis, we show that in the high-frequency terahertz regime where dissipation is harmonic, the quality factor (or loss angle)…
[Phys. Rev. B 95, 054203] Published Mon Feb 13, 2017

Evolution of structure, magnetism, and electronic transport in the doped pyrochlore iridate Y_{2} Ir_{2−x} Ru_{x} O_{7}

2017-02-13T10:00:00-05:00

Author(s): Harish Kumar, R. S. Dhaka, and A. K. Pramanik
The interplay between spin-orbit coupling (SOC) and electron correlation (U) is considered for many exotic phenomena in iridium oxides. We have investigated the evolution of structural, magnetic, and electronic properties in the pyrochlore iridate Y_{2}Ir_{2−x}Ru_{x}O_{7} where the substitution of R…
[Phys. Rev. B 95, 054415] Published Mon Feb 13, 2017

Coherent transport properties of a three-terminal hybrid superconducting interferometer

2017-02-13T10:00:00-05:00

Author(s): F. Vischi, M. Carrega, E. Strambini, S. D'Ambrosio, F. S. Bergeret, Yu. V. Nazarov, and F. Giazotto
We present an exhaustive theoretical analysis of a double-loop Josephson proximity interferometer, such as the one recently realized by Strambini et al. for control of the Andreev spectrum via an external magnetic field. This system, called ω-SQUIPT, consists of a T-shaped diffusive normal metal (N)…
[Phys. Rev. B 95, 054504] Published Mon Feb 13, 2017

Superfluidity in Bose-Hubbard circuits

2017-02-13T10:00:00-05:00

Author(s): Geva Arwas and Doron Cohen
A semiclassical theory is provided for the metastability regime diagram of atomtronic superfluid circuits. Such circuits typically exhibit high-dimensional chaos, and nonlinear resonances that couple the Bogoliubov excitations manifest. Contrary to the expectation, these resonances do not originate …
[Phys. Rev. B 95, 054505] Published Mon Feb 13, 2017

Emergent local integrals of motion without a complete set of localized eigenstates

2017-02-13T10:00:00-05:00

Author(s): Scott D. Geraedts, R. N. Bhatt, and Rahul Nandkishore
Systems where all energy eigenstates are localized are known to display an emergent local integrability, in the sense that one can construct an extensive number of operators that commute with the Hamiltonian and are localized in real space. Here we show that emergent local integrability does not req…
[Phys. Rev. B 95, 064204] Published Mon Feb 13, 2017

Landau-Zener transition driven by slow noise

2017-02-13T10:00:00-05:00

Author(s): Zhu-Xi Luo and M. E. Raikh
The effect of a slow noise in nondiagonal matrix element J(t) that describes the diabatic level coupling on the probability of the Landau-Zener transition is studied. For slow noise, the correlation time τ_{c} of J(t) is much longer than the characteristic time of the transition. Existing theory for…
[Phys. Rev. B 95, 064305] Published Mon Feb 13, 2017

Thermal conductivity of local moment models with strong spin-orbit coupling

2017-02-13T10:00:00-05:00

Author(s): Georgios L. Stamokostas, Panteleimon E. Lapas, and Gregory A. Fiete
We study the magnetic and lattice contributions to the thermal conductivity of electrically insulating strongly spin-orbit coupled magnetically ordered phases on a two-dimensional honeycomb lattice using the Kitaev-Heisenberg model. Depending on model parameters, such as the relative strength of the…
[Phys. Rev. B 95, 064410] Published Mon Feb 13, 2017

Determining the first-order character of La(Fe,Mn,Si)_{13}

2017-02-13T10:00:00-05:00

Author(s): Milan Bratko, Edmund Lovell, A. David Caplin, Vittorio Basso, Alexander Barcza, Matthias Katter, and Lesley F. Cohen
Definitive determination of first-order character of the magnetocaloric magnetic transition remains elusive. Here we use a microcalorimetry technique in two modes of operation to determine the contributions to entropy change from latent heat and heat capacity separately in an engineered set of La(Fe…
[Phys. Rev. B 95, 064411] Published Mon Feb 13, 2017

Magnetic properties of the S=1/2 honeycomb lattice antiferromagnet 2−Cl−3,6−F_{2} −V

2017-02-13T10:00:00-05:00

Author(s): Toshiki Okabe, Hironori Yamaguchi, Shunichiro Kittaka, Toshiro Sakakibara, Toshio Ono, and Yuko Hosokoshi
We successfully synthesized single crystals of the verdazyl radical 2−Cl−3,6−F_{2}−V [=3-(2-chloro-3,6-difluorophenyl)-1,5-diphenylverdazyl], which is a rare model compound with an S=1/2 Heisenberg antiferromagnetic (HAF) honeycomb lattice. Ab initio molecular orbital calculations indicate two domin…
[Phys. Rev. B 95, 075120] Published Mon Feb 13, 2017

Thermodynamic anomaly above the superconducting critical temperature in the quasi-one-dimensional superconductor Ta_{4} Pd_{3} Te_{16}

2017-02-13T10:00:00-05:00

Author(s): T. Helm, F. Flicker, R. Kealhofer, P. J. W. Moll, I. M. Hayes, N. P. Breznay, Z. Li, S. G. Louie, Q. R. Zhang, L. Balicas, J. E. Moore, and J. G. Analytis
We study the intrinsic electronic anisotropy and fermiology of the quasi-one-dimensional superconductor Ta_{4}Pd_{3}Te_{16}. Below T^{*}=20 K, we detect a thermodynamic phase transition that predominantly affects the conductivity perpendicular to the quasi-one-dimensional chains. The transition rela…
[Phys. Rev. B 95, 075121] Published Mon Feb 13, 2017

Nonequilibrium dynamics of a system with two kinds of fermions after a pulse

2017-02-13T10:00:00-05:00

Author(s): A. A. Zvyagin
The nonequilibrium evolution of the system of two kinds of fermions under the action of a pulse of the external field has been studied. The number of fermions of each kind oscillates (with beats and decaying) as a function of the duration of the pulse about the value determined by the magnitude of t…
[Phys. Rev. B 95, 075122] Published Mon Feb 13, 2017

Interaction effects in a chaotic graphene quantum billiard

2017-02-13T10:00:00-05:00

Author(s): Imre Hagymási, Péter Vancsó, András Pálinkás, and Zoltán Osváth
We investigate the local electronic structure of a Sinai-like, quadrilateral graphene quantum billiard with zigzag and armchair edges using scanning tunneling microscopy (STM) at room temperature. It is revealed that besides the (sqrt[3]×sqrt[3])R30^{∘} superstructure, which is caused by the interva…
[Phys. Rev. B 95, 075123] Published Mon Feb 13, 2017

Mott transition and magnetism of the triangular-lattice Hubbard model with next-nearest-neighbor hopping

2017-02-13T10:00:00-05:00

Author(s): Kazuma Misumi, Tatsuya Kaneko, and Yukinori Ohta
The variational cluster approximation is used to study the isotropic triangular-lattice Hubbard model at half filling, taking into account the nearest-neighbor (t_{1}) and next-nearest-neighbor (t_{2}) hopping parameters for magnetic frustrations. We determine the ground-state phase diagram of the m…
[Phys. Rev. B 95, 075124] Published Mon Feb 13, 2017

Phase ordering kinetics of a nonequilibrium exciton-polariton condensate

2017-02-13T10:00:00-05:00

Author(s): Michał Kulczykowski and Michał Matuszewski
We investigate the process of coarsening via annihilation of vortex-antivortex pairs, following the quench to the condensate phase in a nonresonantly pumped polariton system. We find that the late-time dynamics is an example of universal phase-ordering kinetics, characterized by scaling of correlati…
[Phys. Rev. B 95, 075306] Published Mon Feb 13, 2017

Quantum metrology with a single spin-3/2 defect in silicon carbide

2017-02-13T10:00:00-05:00

Author(s): Ö. O. Soykal and T. L. Reinecke
We show that implementations for quantum sensing with exceptional sensitivity and spatial resolution can be made using spin-3/2 semiconductor defect states. We illustrate this using the silicon monovacancy deep center in hexagonal SiC based on our rigorous derivation of this defect's ground state an…
[Phys. Rev. B 95, 081405(R)] Published Mon Feb 13, 2017

Tuning the terahertz low-energy charge dynamics by simultaneous effect of epitaxial and anisotropic strain in PrNiO_{3} thin films

2017-02-13T10:00:00-05:00

Author(s): V. Eswara Phanindra, Sarmistha Das, K. Santhosh Kumar, Piyush Agarwal, Rakesh Rana, and D. S. Rana
The interplay of charge, spin, and lattice correlations strongly influence the insulator-metal (I-M) transition and magnetic ordering in rare earth nickelates. In this context, we explored the low-energy charge dynamics in structurally modulated PrNiO_{3} (PNO) thin films to unravel the complexity o…
[Phys. Rev. B 95, 085114] Published Mon Feb 13, 2017

Magnetic impurities in spin-split superconductors

2017-02-13T10:00:00-05:00

Author(s): W.-V. van Gerven Oei, D. Tanasković, and R. Žitko
Hybrid semiconductor-superconductor quantum dot devices are tunable physical realizations of quantum impurity models for a magnetic impurity in a superconducting host. The binding energy of the localized subgap Shiba states is set by the gate voltages and external magnetic field. In this work we dis…
[Phys. Rev. B 95, 085115] Published Mon Feb 13, 2017

Two-electron bound states near a Coulomb impurity in gapped graphene

2017-02-13T10:00:00-05:00

Author(s): Alessandro De Martino and Reinhold Egger
We formulate and solve the perhaps simplest two-body bound-state problem for interacting Dirac fermions in two spatial dimensions. A two-body bound state is predicted for gapped graphene monolayers in the presence of weakly repulsive electron-electron interactions and a Coulomb impurity with charge …
[Phys. Rev. B 95, 085418] Published Mon Feb 13, 2017

Plasmon properties and hybridization effects in silicene

2017-02-13T10:00:00-05:00

Author(s): C. Vacacela Gomez, M. Pisarra, M. Gravina, P. Riccardi, and A. Sindona
The plasmonic character of monolayer silicene is investigated by time-dependent density functional theory in the random phase approximation. Both the intrinsic (undoped) and several extrinsic (carrier doped or gated) conditions are explored by simulating injection of a probe particle (i.e., an elect…
[Phys. Rev. B 95, 085419] Published Mon Feb 13, 2017

Quasilossless acoustic transmission in an arbitrary pathway of a network

2017-02-10T10:00:00-05:00

Author(s): Hongqing Dai, Tingting Liu, Baizhan Xia, and Dejie Yu
Acoustic metamaterials have exhibited extraordinary potential for manipulating the propagation of sound waves. To date, it has been a challenge to control the propagation of a sound wave through arbitrary pathways in a network. Here, we design a symmetry-breaking, cross-shaped metamaterial comprisin…
[Phys. Rev. B 95, 054109] Published Fri Feb 10, 2017

Characterizing many-body localization by out-of-time-ordered correlation

2017-02-10T10:00:00-05:00

Author(s): Rong-Qiang He and Zhong-Yi Lu

The out-of-time-ordered (OTO) correlation is unconventional. It is a key quantity for quantifying quantum chaoticity and has been recently used in the investigation of quantum holography. On the other hand, it is difficult to reveal and understand the special features of many-body localization (MBL) by conventional quantities and methods. Here, the authors demonstrate that OTO correlation can provide a pertinent and comprehensive description for MBL. It readily reveals the special logarithmic dynamics of MBL, distinguishes MBL sharply from Anderson localization as well as ergodic states, and allows accurate extraction of localization lengths for MBL. The divergence of the localization length at a finite interaction predicts an ergodic-MBL transition. Furthermore, the infinite-time “thermal” fluctuation of the OTO correlation is zero (finite) in the ergodic (MBL) phase and thus can be considered as an order parameter for the ergodic-MBL transition, through which the transition can be identified and characterized. Specifically, the critical point and related critical exponents can be calculated.

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[Phys. Rev. B 95, 054201] Published Fri Feb 10, 2017

Non-Fermi surface nesting driven commensurate magnetic ordering in Fe-doped Sr_{2} RuO_{4}

2017-02-10T10:00:00-05:00

Author(s): M. Zhu, K. V. Shanavas, Y. Wang, T. Zou, W. F. Sun, W. Tian, V. O. Garlea, A. Podlesnyak, M. Matsuda, M. B. Stone, D. Keavney, Z. Q. Mao, D. J. Singh, and X. Ke
Sr_{2}RuO_{4}, an unconventional superconductor, is known to possess an incommensurate spin-density wave instability driven by Fermi surface nesting. Here we report a static spin-density wave ordering with a commensurate propagation vector q_{c}=(0.250.250) in Fe-doped Sr_{2}RuO_{4}, despite the mag…
[Phys. Rev. B 95, 054413] Published Fri Feb 10, 2017

G-type magnetic order in ferropnictide Cu_{x} Fe_{1−y} As induced by hole doping on As sites

2017-02-10T10:00:00-05:00

Author(s): T. Zou, C. C. Lee, W. Tian, H. B. Cao, M. Zhu, B. Qian, C. R. dela Cruz, W. Ku, Z. Q. Mao, and X. Ke
Strong antiferromagnetic (AFM) correlation has long been postulated to be closely related to the occurrence of unconventional high-temperature superconductivity observed in the cuprates, heavy fermions, and organic superconductors. The recently discovered Fe-based superconductors add another interes…
[Phys. Rev. B 95, 054414] Published Fri Feb 10, 2017

Publisher's Note: Phase-resolved detection of the spin Hall angle by optical ferromagnetic resonance in perpendicularly magnetized thin films [Phys. Rev. B 95, 064401 (2017)]

2017-02-10T10:00:00-05:00

Author(s): Amir Capua, Tianyu Wang, See-Hun Yang, Charles Rettner, Timothy Phung, and Stuart S. P. Parkin

[Phys. Rev. B 95, 059901] Published Fri Feb 10, 2017