Preview: Recent Articles in Phys. Rev. B
Recent Articles in Phys. Rev. B
Recent articles in Physical Review B
Published: 2016-12-02T13:45:08-05:00
Domain wall motion and precursor dynamics in PbZrO_{3}
2016-12-02T10:00:00-05:00
Author(s): S. Puchberger, V. Soprunyuk, A. Majchrowski, K. Roleder, and W. Schranz
Single crystals of PbZrO_{3} have been studied by dynamic mechanical analysis measurements in the low-frequency range f=0.02–50 Hz. The complex Young's modulus exhibits a quite rich behavior and depends strongly on the direction of the applied dynamic force. In pseudocubic [100]_{c} direction, we fo…
[Phys. Rev. B 94, 214101] Published Fri Dec 02, 2016
Finite-temperature calculations of the Compton profile of Be, Li, and Si
2016-12-02T10:00:00-05:00
Author(s): E. Klevak, F. D. Vila, J. J. Kas, J. J. Rehr, and G. T. Seidler
High resolution inelastic x-ray scattering experiments are widely used to study the electronic and chemical properties of materials under a range of conditions, from ambient temperature to the warm dense matter regime. We use the real-space multiple scattering (RSMS) Green's function formalism coupl…
[Phys. Rev. B 94, 214201] Published Fri Dec 02, 2016
Tailoring noncollinear magnetism by misfit dislocation lines
2016-12-02T10:00:00-05:00
Author(s): Aurore Finco, Pin-Jui Hsu, André Kubetzka, Kirsten von Bergmann, and Roland Wiesendanger
The large epitaxial stress induced by the misfit between a triple atomic layer Fe film and an Ir(111) substrate is relieved by the formation of a dense dislocation line network. Spin-polarized scanning tunneling microscopy investigations show that the strain is locally varying within the Fe film and…
[Phys. Rev. B 94, 214402] Published Fri Dec 02, 2016
Strain phase separation: Formation of ferroelastic domain structures
2016-12-02T10:00:00-05:00
Author(s): Fei Xue, Yongjun Li, Yijia Gu, Jinxing Zhang, and Long-Qing Chen
Phase decomposition is a well-known process leading to the formation of two-phase mixtures. Here we show that a strain imposed on a ferroelastic crystal promotes the formation of mixed phases and domains, i.e., strain phase separation with local strains determined by a common tangent construction on…
[Phys. Rev. B 94, 220101(R)] Published Fri Dec 02, 2016
ESR study of the frustrated S=1/2 chain magnet LiCuVO_{4} in spiral and spin-modulated phases
2016-12-02T10:00:00-05:00
Author(s): L. A. Prozorova, L. E. Svistov, A. M. Vasiliev, and A. Prokofiev
We report on the electron spin resonance (ESR) study of LiCuVO_{4} in spiral and spin-modulated phases (07.5 T) has two branches. One of them can be explained by uniform oscillations of spin structure, whereas the second branch, surprisingly demonstrates only a weak dependence on field orientation, …
[Phys. Rev. B 94, 224402] Published Fri Dec 02, 2016
Local theory for Mott-Anderson localization
2016-12-02T10:00:00-05:00
Author(s): Sudeshna Sen, Hanna Terletska, Juana Moreno, N. S. Vidhyadhiraja, and Mark Jarrell
The paramagnetic metallic phase of the Anderson-Hubbard model (AHM) is investigated using a nonperturbative local moment approach within the framework of dynamical mean-field theory with a typical medium. Our focus is on the breakdown of the metallic phase near the metal-insulators transition as see…
[Phys. Rev. B 94, 235104] Published Fri Dec 02, 2016
Coherent hole propagation in an exactly solvable gapless spin liquid
2016-12-02T10:00:00-05:00
Author(s): Gábor B. Halász and J. T. Chalker
We examine the dynamics of a single hole in the gapless phase of the Kitaev honeycomb model, focusing on the slow-hole regime where the bare hopping amplitude t is much less than the Kitaev exchange energy J. In this regime, the hole does not generate gapped flux excitations and is dressed only by t…
[Phys. Rev. B 94, 235105] Published Fri Dec 02, 2016
Role of multilevel states on quantum-dot emission in photonic-crystal cavities
2016-12-02T10:00:00-05:00
Author(s): K. H. Madsen, T. B. Lehmann, and P. Lodahl
Semiconductor quantum dots embedded in photonic-crystal nanostructures have been the subject of intense study. In this context, quantum dots are often considered to be simple two-level emitters, i.e., the complexities arising from the internal fine structure are neglected. We show that due to the in…
[Phys. Rev. B 94, 235301] Published Fri Dec 02, 2016
Microscopic theory of equilibrium polariton condensates
2016-12-02T10:00:00-05:00
Author(s): Fei Xue, Fengcheng Wu, Ming Xie, Jung-Jung Su, and A. H. MacDonald
Exciton-polariton condensates have been realized by illuminating a microcavity system containing 2D quantum wells. When the polariton scattering rates exceed polariton lifetimes, the polariton condensate states can be described microscopically using equilibrium statistical mechanics. This work describes a fully microscopic mean-field theory of equilibrium polariton condensates that treats quantum well band states explicitly and goes beyond the commonly used model in which excitons are treated as Bose particles that are coupled to cavity photons. The authors compare their results with the predictions of simplified bosonic theory, and explain the quantitative differences in condensate properties. Their theory predicts that effective polariton-polariton interaction strengths are weaker and that exciton-fractions in the condensate are smaller than in the simplified exciton-photon model, and that the effective Rabi coupling strengths depends on detuning. The quasiparticle bands that appear in their theory are dressed by both electron-electron and electron-photon interactions, with the electron-electron contribution dominating even when the photon fraction of the condensate is relatively large. The properties of the dressed bands suggest novel mechanisms for the electrical manipulation of polariton condensates.
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[Phys. Rev. B 94, 235302] Published Fri Dec 02, 2016
Mechanical actuation of graphene sheets via optically induced forces
2016-12-02T10:00:00-05:00
Author(s): Mohammad Mahdi Salary, Sandeep Inampudi, Kuan Zhang, Ellad B. Tadmor, and Hossein Mosallaei
In this paper, we theoretically demonstrate the strong mechanical response of graphene sheets actuated by near-field optical forces. We study single-layer graphene and a two-layer graphene stack with large separation and show that tunable attractive and repulsive forces can be generated. A large non…
[Phys. Rev. B 94, 235403] Published Fri Dec 02, 2016
Infrared spectroscopic study of carrier scattering in gated CVD graphene
2016-12-02T10:00:00-05:00
Author(s): Kwangnam Yu, Jiho Kim, Joo Youn Kim, Wonki Lee, Jun Yeon Hwang, E. H. Hwang, and E. J. Choi
We measured Drude absorption of gated CVD graphene using far-infrared transmission spectroscopy and determined the carrier scattering rate (γ) as a function of the varied carrier density (n). The n-dependent γ(n) was obtained for a series of conditions systematically changed as (10 K, vacuum) → (300…
[Phys. Rev. B 94, 235404] Published Fri Dec 02, 2016
Thermodynamic meaning of local temperature of nonequilibrium open quantum systems
2016-12-02T10:00:00-05:00
Author(s): LvZhou Ye, Xiao Zheng, YiJing Yan, and Massimiliano Di Ventra
Measuring the local temperature of nanoscale systems out of equilibrium has emerged as a new tool to study local heating effects and other local thermal properties of systems driven by external fields. Although various experimental protocols and theoretical definitions have been proposed to determin…
[Phys. Rev. B 94, 245105] Published Fri Dec 02, 2016
Emergence of an excitonic collective mode in the dilute electron gas
2016-12-02T10:00:00-05:00
Author(s): Yasutami Takada
In the early 1950s, Bohm and Pines (BP) developed the random-phase approximation (RPA) theory and revealed the plasmon as an emergent collective mode in metals. In this paper, for the first time ever since the original BP theory, a novel collective mode is predicted to emerge in the dilute electron liquid. The electronic compressibility of this mode is negative and thus dielectric catastrophe appears, predicted by a theory that goes far beyond RPA and fully satisfies various sum rules, constraints, and asymptotic behavior. While the plasmon occurs by the coherent excitations of mutually uncorrelated electrons and holes, the new mode is associated with the excitations of a large collection of excitons (or tightly bound electron-hole pairs). Mathematically, this excitonic collective mode is intimately connected with a newly discovered singularity in the dielectric function in the electron liquid. This collective mode should add a new dimension to plasmonics in nanotechnology in the future.
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[Phys. Rev. B 94, 245106] Published Fri Dec 02, 2016
Strain-induced g-factor tuning in single InGaAs/GaAs quantum dots
2016-12-02T10:00:00-05:00
Author(s): H. M. G. A. Tholen, J. S. Wildmann, A. Rastelli, R. Trotta, C. E. Pryor, E. Zallo, O. G. Schmidt, P. M. Koenraad, and A. Yu. Silov
The tunability of the exciton g factor in InGaAs quantum dots using compressive biaxial stress applied by piezoelectric actuators is investigated. We find a clear relation between the exciton g factor and the applied stress. A linear decrease of the g factor with compressive biaxial strain is observ…
[Phys. Rev. B 94, 245301] Published Fri Dec 02, 2016
Electron-phonon scattering and in-plane electric conductivity in twisted bilayer graphene
2016-12-02T10:00:00-05:00
Author(s): N. Ray, M. Fleischmann, D. Weckbecker, S. Sharma, O. Pankratov, and S. Shallcross
We have surveyed the in-plane transport properties of the graphene twist bilayer using (i) a low-energy effective Hamiltonian for the underlying electronic structure, (ii) an isotropic elastic phonon model, and (iii) the linear Boltzmann equation for elastic electron-phonon scattering. We find that …
[Phys. Rev. B 94, 245403] Published Fri Dec 02, 2016
Dephasing in strongly anisotropic black phosphorus
2016-12-02T10:00:00-05:00
Author(s): N. Hemsworth, V. Tayari, F. Telesio, S. Xiang, S. Roddaro, M. Caporali, A. Ienco, M. Serrano-Ruiz, M. Peruzzini, G. Gervais, T. Szkopek, and S. Heun
Weak localization was observed in a black phosphorus field-effect transistor 65 nm thick. The weak localization behavior was found to be in excellent agreement with the Hikami-Larkin-Nagaoka model for fields up to 1 T, from which characteristic scattering lengths could be inferred. The temperature d…
[Phys. Rev. B 94, 245404] Published Fri Dec 02, 2016
Spin-valley caloritronics in silicene near room temperature
2016-12-02T10:00:00-05:00
Author(s): Xuechao Zhai, Wenwen Gao, Xinlong Cai, Ding Fan, Zhihong Yang, and Lan Meng
Two-dimensional silicene, with an observable intrinsic spin-orbit coupling, has a great potential to perform fascinating physics and new types of applications in spintronics and valleytronics. By introducing an electromotive force from a temperature difference in ferromagnetic silicene, we discover …
[Phys. Rev. B 94, 245405] Published Fri Dec 02, 2016
Superconductivity in repulsively interacting fermions on a diamond chain: Flat-band-induced pairing
2016-12-01T10:00:00-05:00
Author(s): Keita Kobayashi, Masahiko Okumura, Susumu Yamada, Masahiko Machida, and Hideo Aoki
To explore whether a flat-band system can accommodate superconductivity, we consider repulsively interacting fermions on the diamond chain, a simplest possible quasi-one-dimensional system that contains a flat band. Exact diagonalization and the density-matrix renormalization group are used to show …
[Phys. Rev. B 94, 214501] Published Thu Dec 01, 2016
Phenomenological approach to a hyperkagome spin liquid: Emergent gauge fields and spinons
2016-12-01T10:00:00-05:00
Author(s): Yuan Wan and Yong Baek Kim
A number of experiments on the hyperkagome iridate, Na_{4}Ir_{3}O_{8}, suggest existence of a gapless quantum spin liquid state at low temperature. Circumventing the slave-particle approach commonly used in theoretical analyses of frustrated magnets, we provide a more intuitive, albeit more phenomen…
[Phys. Rev. B 94, 224401] Published Thu Dec 01, 2016
Theory of spin-selective Andreev reflection in the vortex core of a topological superconductor
2016-12-01T10:00:00-05:00
Author(s): Lun-Hui Hu, Chuang Li, Dong-Hui Xu, Yi Zhou, and Fu-Chun Zhang
Majorana zero modes (MZMs) have been predicted to exist in a topological insulator (TI)/superconductor (SC) heterostructure. A recent spin-polarized scanning tunneling microscope (STM) experiment [Sun et al., Phys. Rev. Lett. 116, 257003 (2016)] has observed a spin-polarization dependence of the ze…
[Phys. Rev. B 94, 224501] Published Thu Dec 01, 2016
Many-terminal Majorana island: From topological to multichannel Kondo model
2016-12-01T10:00:00-05:00
Author(s): Loïc Herviou, Karyn Le Hur, and Christophe Mora
The Kondo effect refers to a localized spin impurity that is screened by conduction electrons at low temperatures, leading to entanglement and nontrivial transport properties. Connecting zero-energy Majorana bound states of a charge-quantized superconducting island to $M$ normal metallic leads realizes exotic SO($M$) Kondo models with mesoscopic systems. In the Coulomb-blockade regime, the Majorana fermions lead to a family of non-Fermi-liquid fixed points and symmetric correlated transport between the leads, dubbed the topological Kondo effect (TKE). This work brings light to the resonant limit, where the charging energy selects two consecutive macroscopic charge states. The interplay between the charge states and the Majorana fermions allows for an exact mapping to the interacting multichannel Kondo model (MCKM). The quantum Brownian motion analogy proves the existence of a continuously varying line of fixed points between the MCKM and the TKE, characterized by fractional conductance, depending on the electron-electron interactions in the leads.
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[Phys. Rev. B 94, 235102] Published Thu Dec 01, 2016
Low-temperature Hall effect in bismuth chalcogenides thin films
2016-12-01T10:00:00-05:00
Author(s): A. Yu. Kuntsevich, A. A. Gabdullin, V. A. Prudkogliad, Yu. G. Selivanov, E. G. Chizhevskii, and V. M. Pudalov
Bismuth chalcogenides are the most studied 3D topological insulators. As a rule, at low temperatures, thin films of these materials demonstrate positive magnetoresistance due to weak antilocalization. Weak antilocalization should lead to resistivity decrease at low temperatures; in experiments, howe…
[Phys. Rev. B 94, 235401] Published Thu Dec 01, 2016
Nonlinear response of bilayer graphene at terahertz frequencies
2016-12-01T10:00:00-05:00
Author(s): Riley McGouran, Ibraheem Al-Naib, and Marc M. Dignam
A density-matrix formalism within the length gauge is developed for the purpose of calculating the nonlinear response of intrinsic bilayer graphene at terahertz frequencies. Employing a tight-binding model, we find that the interplay between the interband and intraband dynamics leads to strong harmo…
[Phys. Rev. B 94, 235402] Published Thu Dec 01, 2016
Electrodynamic response of the type-II Weyl semimetal YbMnBi_{2}
2016-12-01T10:00:00-05:00
Author(s): M. Chinotti, A. Pal, W. J. Ren, C. Petrovic, and L. Degiorgi
Weyl fermions play a major role in quantum field theory but have been quite elusive as fundamental particles. Materials based on quasi-two-dimensional bismuth layers were recently designed and provide an arena for studying the interplay between anisotropic Dirac fermions, magnetism, and structural c…
[Phys. Rev. B 94, 245101] Published Thu Dec 01, 2016
Ising and Gross-Neveu model in next-to-leading order
2016-12-01T10:00:00-05:00
Author(s): Benjamin Knorr
We study scalar and chiral fermionic models in next-to-leading order with the help of the functional renormalization group. Their critical behavior is of special interest in condensed-matter systems, in particular graphene. To derive the β functions, we make extensive use of computer algebra. The re…
[Phys. Rev. B 94, 245102] Published Thu Dec 01, 2016
Local quench, Majorana zero modes, and disturbance propagation in the Ising chain
2016-12-01T10:00:00-05:00
Author(s): G. Francica, T. J. G. Apollaro, N. Lo Gullo, and F. Plastina
We study the generation and propagation of local perturbations in a quantum many-body spin system. In particular, we study the Ising model in transverse field in the presence of a local field defect at one edge. This system possesses a rich phase diagram with different regions characterized by the p…
[Phys. Rev. B 94, 245103] Published Thu Dec 01, 2016
Lattice effects on Laughlin wave functions and parent Hamiltonians
2016-12-01T10:00:00-05:00
Author(s): Ivan Glasser, J. Ignacio Cirac, Germán Sierra, and Anne E. B. Nielsen
We investigate lattice effects on wave functions that are lattice analogs of bosonic and fermionic Laughlin wave functions with number of particles per flux ν=1/q in the Landau levels. These wave functions are defined analytically on lattices with μ particles per lattice site, where μ may be differe…
[Phys. Rev. B 94, 245104] Published Thu Dec 01, 2016
Theory of condensation of indirect excitons in a trap
2016-12-01T10:00:00-05:00
Author(s): S. V. Lobanov, N. A. Gippius, and L. V. Butov
We present theoretical studies of condensation of indirect excitons in a trap. Our model quantifies the effect of screening of the trap potential by indirect excitons on exciton condensation. The theoretical studies are applied to a system of indirect excitons in a GaAs/AlGaAs coupled quantum well s…
[Phys. Rev. B 94, 245401] Published Thu Dec 01, 2016
Pressure- and temperature-driven phase transitions in HgTe quantum wells
2016-12-01T10:00:00-05:00
Author(s): S. S. Krishtopenko, I. Yahniuk, D. B. But, V. I. Gavrilenko, W. Knap, and F. Teppe
We present theoretical investigations of pressure- and temperature-driven phase transitions in HgTe quantum wells grown on a CdTe buffer. Using the eight-band k·p Hamiltonian we calculate evolution of energy-band structure at different quantum well widths with hydrostatic pressure up to 20 kbars and…
[Phys. Rev. B 94, 245402] Published Thu Dec 01, 2016
Multichiral ground states in mesoscopic p-wave superconductors
2016-11-30T10:00:00-05:00
Author(s): V. Fernández Becerra and M. V. Milošević
Using Ginzburg-Landau formalism, we investigate the effect of confinement on the ground state of mesoscopic chiral p-wave superconductors in the absence of magnetic field. We reveal stable multichiral states with domain walls separating the regions with different chiralities, as well as monochiral s…
[Phys. Rev. B 94, 184517] Published Wed Nov 30, 2016
Magnetic structures and excitations in a multiferroic Y-type hexaferrite BaSrCo_{2} Fe_{11} AlO_{22}
2016-11-30T10:00:00-05:00
Author(s): Taro Nakajima, Yusuke Tokunaga, Masaaki Matsuda, Sachith Dissanayake, Jaime Fernandez-Baca, Kazuhisa Kakurai, Yasujiro Taguchi, Yoshinori Tokura, and Taka-hisa Arima
Multiferroic hexaferrites have been extensively investigated because they exhibit ferroelectricity associated with noncollinear magnetic orders in relatively low magnetic field and high temperature regions. To understand the static and dynamical spin-polarization coupling in such systems, it is necessary to determine the magnetic structures and spin-wave modes. This is impossible for polycrystalline samples. Here, the authors have successfully grown single crystals of BaSrCo${}_{2}$Fe${}_{12}$AlO${}_{22}$ by means of a laser floating zone technique. They perform magnetization, electric polarization, and neutron diffraction measurements to establish the magnetic phase diagram. Several interesting features are seen and the new understanding should provide a useful guide for developing multiferroic-based functional devices working at room temperature.
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[Phys. Rev. B 94, 195154] Published Wed Nov 30, 2016
Electronic structure and magnetism of strained bcc phases across the fcc to bcc transition in ultrathin Fe films
2016-11-30T10:00:00-05:00
Author(s): Alberto Calloni, Giulia Berti, Gianlorenzo Bussetti, Guido Fratesi, Marco Finazzi, Franco Ciccacci, and Lamberto Duò
We investigated the electronic structure of the bcc metastable phases involved in the fcc to bcc transition of Fe. Ultrathin Fe films were grown on a 2-monolayer (ML) Ni/W(110) substrate, where a fcc lattice is stabilized at low Fe coverages and the transition proceeds through the formation of bcc n…
[Phys. Rev. B 94, 195155] Published Wed Nov 30, 2016
Optical probe of Heisenberg-Kitaev magnetism in α−RuCl_{3}
2016-11-30T10:00:00-05:00
Author(s): Luke J. Sandilands, C. H. Sohn, H. J. Park, So Yeun Kim, K. W. Kim, Jennifer A. Sears, Young-June Kim, and Tae Won Noh
We report a temperature-dependent optical spectroscopic study of the Heisenberg-Kitaev magnet α−RuCl_{3}. Our measurements reveal anomalies in the optical response near the magnetic ordering temperature. At higher temperatures, we observe a redistribution of spectral weight over a broad energy range…
[Phys. Rev. B 94, 195156] Published Wed Nov 30, 2016
Lorentz force effects for graphene Aharonov-Bohm interferometers
2016-11-30T10:00:00-05:00
Author(s): A. Mreńca-Kolasińska and B. Szafran
We investigate magnetic deflection of currents that flow across the Aharonov-Bohm interferometers defined in graphene. We consider devices induced by closed n−p junctions in nanoribbons as well as etched quantum rings. The deflection effects on conductance are strictly correlated with the properties…
[Phys. Rev. B 94, 195315] Published Wed Nov 30, 2016
Second-order nonlinear optical response of graphene
2016-11-30T10:00:00-05:00
Author(s): Yongrui Wang, Mikhail Tokman, and Alexey Belyanin
Although massless Dirac fermions in graphene constitute a centrosymmetric medium for in-plane excitations, their second-order nonlinear optical response is nonzero if the effects of spatial dispersion are taken into account. Here we present a rigorous quantum-mechanical theory of the second-order no…
[Phys. Rev. B 94, 195442] Published Wed Nov 30, 2016
Anomalies and symmetry fractionalization in reflection-symmetric topological order
2016-11-30T10:00:00-05:00
Author(s): Ethan Lake
One of the central ideas regarding anomalies in topological phases of matter is that they imply the existence of higher-dimensional physics, with an anomaly in a D-dimensional theory typically being canceled by a bulk (D+1)-dimensional symmetry-protected topological phase (SPT). We demonstrate that …
[Phys. Rev. B 94, 205149] Published Wed Nov 30, 2016
Matrix product operators for symmetry-protected topological phases: Gauging and edge theories
2016-11-30T10:00:00-05:00
Author(s): Dominic J. Williamson, Nick Bultinck, Michael Mariën, Mehmet B. Şahinoğlu, Jutho Haegeman, and Frank Verstraete
Projected entangled pair states (PEPS) provide a natural ansatz for the ground states of gapped, local Hamiltonians in which global characteristics of a quantum state are encoded in properties of local tensors. We develop a framework to describe onsite symmetries, as occurring in systems exhibiting …
[Phys. Rev. B 94, 205150] Published Wed Nov 30, 2016
Transparency of graphene and other direct-gap two-dimensional materials
2016-11-30T10:00:00-05:00
Author(s): Daniel J. Merthe and Vitaly V. Kresin
The optical properties of graphene are among its remarkable characteristics. Measurements have found that the opacity of a single graphene layer for infrared and visible light is simply equal to $\pi $ times the fine-structure constant. Explanations of this beautiful relation have tended to view it as a consequence of the material’s Dirac-like band structure. However, in this paper the authors emphasize that the interband absorption rate must be treated by using the underlying nonrelativistic Hamiltonian, not the quasimomentum state label of the bands. They employ both a straightforward model and a tight-binding calculation to show that the opacity of graphene follows not from its celebrated linear dispersion relation but from the fact that it is a two-dimensional material. The same characteristic is therefore present in semiconductor membranes (as revealed by recent experiments) and other two-dimensional systems. This work focuses attention on the universality that reduced dimensionality bestows on optical absorption.
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[Phys. Rev. B 94, 205439] Published Wed Nov 30, 2016
Coherence and stiffness of spin waves in diluted ferromagnets
2016-11-29T10:00:00-05:00
Author(s): I. Turek, J. Kudrnovský, and V. Drchal
We present the results of a numerical analysis of magnon spectra in supercells simulating two-dimensional and bulk random diluted ferromagnets with long-range pair exchange interactions. We show that low-energy spectral regions for these strongly disordered systems contain a coherent component leadi…
[Phys. Rev. B 94, 174447] Published Tue Nov 29, 2016
Structure of exciton condensates in imbalanced electron-hole bilayers
2016-11-29T10:00:00-05:00
Author(s): J. R. Varley and D. K. K. Lee
We investigate the possibility of excitonic superfluidity in electron-hole bilayers. We calculate the phase diagram of the system for the whole range of electron-hole density imbalance and for different degrees of electrostatic screening, using mean-field theory and a Ginzburg–Landau expansion. We a…
[Phys. Rev. B 94, 174519] Published Tue Nov 29, 2016
Melting temperature of water: DFT-based molecular dynamics simulations with D3 dispersion correction
2016-11-29T10:00:00-05:00
Author(s): Ari P. Seitsonen and Taras Bryk
Extensive ab initio simulations of ice-water basal interface at seven temperatures in the range 250–400 K were performed in NVT and NPT ensembles with a collection of 389 water molecules in order to estimate the melting point of ice from direct liquid-solid two-phase coexistence. Density functional …
[Phys. Rev. B 94, 184111] Published Tue Nov 29, 2016
Temperature fluctuations in canonical systems: Insights from molecular dynamics simulations
2016-11-29T10:00:00-05:00
Author(s): J. Hickman and Y. Mishin
Molecular dynamics simulations of a quasiharmonic solid are conducted to elucidate the meaning of temperature fluctuations in canonical systems and validate a well-known but frequently contested equation predicting the mean square of such fluctuations. The simulations implement two virtual and one p…
[Phys. Rev. B 94, 184311] Published Tue Nov 29, 2016
Magnetotransport properties of Fe_{0.8} Ga_{0.2} films with stripe domains
2016-11-29T10:00:00-05:00
Author(s): M. Granada, S. Bustingorry, D. E. Pontello, M. Barturen, M. Eddrief, M. Marangolo, and J. Milano
Magnetotransport properties of Fe_{0.8}Ga_{0.2} films with stripe domains are studied. The anisotropic magnetoresistance dominates the low field behavior, which is extremely dependent on the magnetic domains configuration. The magnetoresistance measured at different temperatures displays qualitative…
[Phys. Rev. B 94, 184435] Published Tue Nov 29, 2016
Seebeck coefficient in correlated low-dimensional organic metals
2016-11-29T10:00:00-05:00
Author(s): M. Shahbazi and C. Bourbonnais
We study the influence of inelastic electron-electron scattering on the temperature variation of the Seebeck coefficient in the normal phase of quasi-one-dimensional organic superconductors. The theory is based on the numerical solution of the semiclassical Boltzmann equation for which the collision…
[Phys. Rev. B 94, 195153] Published Tue Nov 29, 2016
Spectroscopic STM studies of single pentacene molecules on Cu(110)−c(6×2)O
2016-11-29T10:00:00-05:00
Author(s): Johannes Gall, Peter Zeppenfeld, Lidong Sun, Li Zhang, Yang Luo, Zhenchao Dong, Chunguang Hu, and Peter Puschnig
Pentacene adsorbed on the Cu(110)−c(6×2)O surface has been investigated using scanning tunneling microscopy and spectroscopy and density functional theory calculations. The molecules lie almost flat on the surface and are anchored via the end carbon ring to a Cu atom of the topmost surface layer, le…
[Phys. Rev. B 94, 195441] Published Tue Nov 29, 2016
Full Stark control of polariton states on a spin-orbit hypersphere
2016-11-29T10:00:00-05:00
Author(s): Feng Li, E. Cancellieri, G. Buonaiuto, M. S. Skolnick, D. N. Krizhanovskii, and D. M. Whittaker
The orbital angular momentum and the polarization of light are physical quantities widely investigated for classical and quantum information processing. In this work we propose to take advantage of strong light-matter coupling, circular-symmetric confinement, and transverse-electric transverse-magne…
[Phys. Rev. B 94, 201301(R)] Published Tue Nov 29, 2016
Monte Carlo study of Dirac semimetals phase diagram
2016-11-29T10:00:00-05:00
Author(s): V. V. Braguta, M. I. Katsnelson, A. Yu. Kotov, and A. A. Nikolaev
In this paper the phase diagram of Dirac semimetals is studied within a lattice Monte Carlo simulation. In particular, we concentrate on the dynamical chiral symmetry breaking which results in a semimetal-insulator transition. Using numerical simulation, we determine the values of the critical coupl…
[Phys. Rev. B 94, 205147] Published Tue Nov 29, 2016
Spectroscopic signatures of molecular orbitals in transition metal oxides with a honeycomb lattice
2016-11-29T10:00:00-05:00
Author(s): Z. V. Pchelkina, S. V. Streltsov, and I. I. Mazin
A tendency to form benzenelike molecular orbitals has recently been shown to be a common feature of the 4d and 5d transition metal oxides with a honeycomb lattice. This tendency competes with other interactions such as the spin-orbit coupling and Hubbard correlations and can be partially or complete…
[Phys. Rev. B 94, 205148] Published Tue Nov 29, 2016
Quantum gates with donors in germanium
2016-11-29T10:00:00-05:00
Author(s): Giuseppe Pica and Brendon W. Lovett
Recent work has shown that electron spins in germanium (Ge) nanoscale transistors can be electrically tuned and have encouraging coherence times. Based on a complete and validated theory of Ge-donor electron states, we propose that Ge spin qubits could have significant advantages over silicon (Si) i…
[Phys. Rev. B 94, 205309] Published Tue Nov 29, 2016
Disorder fingerprint: Intensity distributions in the near field of random media
2016-11-28T10:00:00-05:00
Author(s): R. Rezvani Naraghi, S. Sukhov, and A. Dogariu
The structural morphology of complex dielectric media determines their functionalities by driving the statistical properties of the electromagnetic fields. Our controlled experiments and full electromagnetic calculations that go beyond common dipolar approximations demonstrate that the specific char…
[Phys. Rev. B 94, 174205] Published Mon Nov 28, 2016
Zak phases and band properties in acoustic metamaterials with negative modulus or negative density
2016-11-28T10:00:00-05:00
Author(s): Li Fan, Wei-wei Yu, Shu-yi Zhang, Hui Zhang, and Jin Ding
Zak phases in two types of acoustic metamaterials with negative density or negative modulus are studied. Different from phononic crystals based on Bragg scattering, extraordinary performance in acoustic metamaterials originates from local resonance. We find that the Zak phases in metamaterials are d…
[Phys. Rev. B 94, 174307] Published Mon Nov 28, 2016
Magnetic field-temperature phase diagrams of multiferroic (Ni_{0.9} Co_{0.1} )_{3} V_{2} O_{8}
2016-11-28T10:00:00-05:00
Author(s): N. Qureshi, E. Ressouche, A. A. Mukhin, V. Yu. Ivanov, S. N. Barilo, S. V. Shiryaev, and V. Skumryev
We present macroscopic and neutron diffraction data on multiferroic lightly Co doped Ni_{3}V_{2}O_{8}. The magnetic H−T phase diagrams have been derived from magnetization and electric polarization measurements with field directions parallel to the principal crystallographic axes. While the phase di…
[Phys. Rev. B 94, 174441] Published Mon Nov 28, 2016
Properties of the random-singlet phase: From the disordered Heisenberg chain to an amorphous valence-bond solid
2016-11-28T10:00:00-05:00
Author(s): Yu-Rong Shu, Dao-Xin Yao, Chih-Wei Ke, Yu-Cheng Lin, and Anders W. Sandvik
We use a strong-disorder renormalization group (SDRG) method and ground-state quantum Monte Carlo (QMC) simulations to study S=1/2 spin chains with random couplings, calculating disorder-averaged spin and dimer correlations. The QMC simulations demonstrate logarithmic corrections to the power-law de…
[Phys. Rev. B 94, 174442] Published Mon Nov 28, 2016
Phase diagram of diluted Ising ferromagnet LiHo_{x} Y_{1−x} F_{4}
2016-11-28T10:00:00-05:00
Author(s): P. Babkevich, N. Nikseresht, I. Kovacevic, J. O. Piatek, B. Dalla Piazza, C. Kraemer, K. W. Krämer, K. Prokeš, S. Mat'aš, J. Jensen, and H. M. Rønnow
We present a systematic study of the phase diagram of LiHo_{x}Y_{1−x}F_{4} (0.25≤x≤1) Ising ferromagnets obtained from neutron scattering measurements and mean-field calculations. We show that while the thermal phase transition decreases linearly with dilution, as predicted by mean-field theory, the…
[Phys. Rev. B 94, 174443] Published Mon Nov 28, 2016
Magnetism of epitaxial Tb films on W(110) studied by spin-polarized low-energy electron microscopy
2016-11-28T10:00:00-05:00
Author(s): J. E. Prieto, Gong Chen (陈宫), A. K. Schmid, and J. de la Figuera
Thin epitaxial films of Tb metal were grown on a clean W(110) substrate in ultrahigh vacuum and studied in situ by low-energy electron microscopy. Annealed films present magnetic contrast in spin-polarized low-energy electron microscopy. The energy dependence of the electron reflectivity was determi…
[Phys. Rev. B 94, 174445] Published Mon Nov 28, 2016
Magnetoelectric phase diagrams of multiferroic GdMn_{2} O_{5}
2016-11-28T10:00:00-05:00
Author(s): S. H. Bukhari, Th. Kain, M. Schiebl, A. Shuvaev, Anna Pimenov, A. M. Kuzmenko, X. Wang, S.-W. Cheong, J. Ahmad, and A. Pimenov
Electric and magnetic properties of multiferroic GdMn_{2}O_{5} in external magnetic fields were investigated to map out the magnetoelectric phases in this material. Due to strong magnetoelectric coupling, the dielectric permittivity is highly sensitive to phase boundaries in GdMn_{2}O_{5}, which all…
[Phys. Rev. B 94, 174446] Published Mon Nov 28, 2016
Variation in superconducting transition temperature due to tetragonal domains in two-dimensionally doped SrTiO_{3}
2016-11-28T10:00:00-05:00
Author(s): Hilary Noad, Eric M. Spanton, Katja C. Nowack, Hisashi Inoue, Minu Kim, Tyler A. Merz, Christopher Bell, Yasuyuki Hikita, Ruqing Xu, Wenjun Liu, Arturas Vailionis, Harold Y. Hwang, and Kathryn A. Moler
Strontium titanate is a low-temperature, non–Bardeen-Cooper-Schrieffer superconductor that superconducts to carrier concentrations lower than in any other system and exhibits avoided ferroelectricity at low temperatures. Neither the mechanism of superconductivity in strontium titanate nor the import…
[Phys. Rev. B 94, 174516] Published Mon Nov 28, 2016
Origin of positive out-of-plane magnetoconductivity in overdoped Bi_{1.6} Pb_{0.4} Sr_{2} CaCu_{1.96} Fe_{0.04} O_{8+δ}
2016-11-28T10:00:00-05:00
Author(s): Takao Watanabe, Tomohiro Usui, Shintaro Adachi, Yuki Teramoto, Mihaly M. Dobroka, Itsuhiro Kakeya, Akihiro Kondo, Koichi Kindo, and Shojiro Kimura
To elucidate the pseudogap phase diagram including the overdoped state of high transition temperature (high-T_{c}) cuprates, we must understand the origin of the positive out-of-plane magnetoconductivity observed in these compounds. For this purpose, the out-of-plane resistivity ρ_{c}(T,H) of an ove…
[Phys. Rev. B 94, 174517] Published Mon Nov 28, 2016
Displacement and annihilation of Dirac gap nodes in d-wave iron-based superconductors
2016-11-28T10:00:00-05:00
Author(s): Andrey V. Chubukov, Oskar Vafek, and Rafael M. Fernandes
Several experimental and theoretical arguments have been made in favor of a d-wave symmetry for the superconducting state in some Fe-based materials. It is a common belief that a d-wave gap in the Fe-based superconductors must have nodes on the Fermi surfaces centered at the Γ point of the Brillouin…
[Phys. Rev. B 94, 174518] Published Mon Nov 28, 2016
Interfacial control of Dzyaloshinskii-Moriya interaction in heavy metal/ferromagnetic metal thin film heterostructures
2016-11-28T10:00:00-05:00
Author(s): Xin Ma, Guoqiang Yu, Xiang Li, Tao Wang, Di Wu, Kevin S. Olsson, Zhaodong Chu, Kyongmo An, John Q. Xiao, Kang L. Wang, and Xiaoqin Li
The interfacial Dzyaloshinskii-Moriya interaction (DMI) in ultrathin magnetic thin film heterostructures provides a new approach for controlling spin textures on mesoscopic length scales. Here we investigate the dependence of the interfacial DMI constant D on a Pt wedge insertion layer in Ta/CoFeB/P…
[Phys. Rev. B 94, 180408(R)] Published Mon Nov 28, 2016
Controlling Gilbert damping in a YIG film using nonlocal spin currents
2016-11-28T10:00:00-05:00
Author(s): M. Haidar, P. Dürrenfeld, M. Ranjbar, M. Balinsky, M. Fazlali, M. Dvornik, R. K. Dumas, S. Khartsev, and J. Åkerman
We demonstrate the control of Gilbert damping in 65-nm-thick yttrium iron garnet (YIG) films using a spin-polarized current generated by a direct current through a nanocontact, spin filtered by a thin Co layer. The magnetodynamics of both the YIG and the Co layers can be excited by a pulse-modulated…
[Phys. Rev. B 94, 180409(R)] Published Mon Nov 28, 2016
Ab initio study of deformed As, Sb, and Bi with an application to thin films
2016-11-28T10:00:00-05:00
Author(s): M. Zouhar and M. Šob
We present a comprehensive density-functional theory study of total energy and structural properties of As, Sb, and Bi in their A7 ground-state structure and in the bcc, fcc, and simple cubic (sc) modifications. We also investigate continuous structural transitions between these structures. The elec…
[Phys. Rev. B 94, 184110] Published Mon Nov 28, 2016
Ab initio evidence for nonthermal characteristics in ultrafast laser melting
2016-11-28T10:00:00-05:00
Author(s): Chao Lian, S. B. Zhang, and Sheng Meng
Laser melting of semiconductors has been observed for almost 40 years; surprisingly, it is not well understood where most theoretical simulations show a laser-induced thermal process. Ab initio nonadiabatic simulations based on real-time time-dependent density functional theory reveal intrinsic nont…
[Phys. Rev. B 94, 184310] Published Mon Nov 28, 2016
Direct observation of anisotropic magnetic field response of the spin helix in FeGe thin films
2016-11-28T10:00:00-05:00
Author(s): N. Kanazawa, J. S. White, H. M. Rønnow, C. D. Dewhurst, Y. Fujishiro, A. Tsukazaki, Y. Kozuka, M. Kawasaki, M. Ichikawa, F. Kagawa, and Y. Tokura
Spiral spin orders often produce various fascinating phenomena via interaction with electronic structures. Examples include, but are not limited to, multiferroicity and skyrmion formation. Among them, a deformed spiral spin structure, which can be viewed as a periodic sequence of 2$\pi $ spin-rotation kinks, can exhibit the functionality of information transmission owing to its phase coherence. This is the chiral magnetic soliton lattice (CSL). Here, the authors have succeeded in building a spin spiral in a thin film of the chiral magnet FeGe, and revealed its characteristic magnetic responses. Magnetic anisotropy and boundary conditions inherent to the epitaxial thin film secure the alignment of the spiral winding direction along the film normal, even under external magnetic fields. This constraint leads to the anisotropic deformation of the spin spiral with respect to the magnetic field direction. Especially, the CSL, which is realized under an in-plane magnetic field, transforms with field between states with different numbers of kinks. The authors clearly demonstrate the deformation by direct observation of the spiral propagation vector by use of the small-angle neutron scattering technique.
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[Phys. Rev. B 94, 184432] Published Mon Nov 28, 2016
Element-resolved magnetism across the temperature- and pressure-induced spin reorientation in MnBi
2016-11-28T10:00:00-05:00
Author(s): Yongseong Choi, Xiujuan Jiang, Wenli Bi, Pavel Lapa, Rajiv K. Chouhan, D. Paudyal, Tamas Varga, Dmitry Popov, Jun Cui, Daniel Haskel, and J. S. Jiang
Rare-earth free permanent magnet MnBi (NiAs-type crystal structure) displays strong uniaxial magnetic anisotropy above its ∼90 K spin reorientation transition (SRT). X-ray magnetic circular dichroism (XMCD) measurements at the Mn K and Bi L_{2,3} edges show induced magnetism in Bi, which is strongly…
[Phys. Rev. B 94, 184433] Published Mon Nov 28, 2016
Vortex spectroscopy in the vortex glass: A real-space numerical approach
2016-11-28T10:00:00-05:00
Author(s): C. Berthod
A method is presented to solve the Bogoliubov–de Gennes equations with arbitrary distributions of vortices. The real-space Green's function approach based on Chebyshev polynomials is complemented by a gauge transformation which allows one to treat finite as well as infinite, ordered as well as disor…
[Phys. Rev. B 94, 184510] Published Mon Nov 28, 2016
Direct observation of charge order in underdoped and optimally doped Bi_{2} (Sr,La)_{2} CuO_{6+δ} by resonant inelastic x-ray scattering
2016-11-28T10:00:00-05:00
Author(s): Y. Y. Peng, M. Salluzzo, X. Sun, A. Ponti, D. Betto, A. M. Ferretti, F. Fumagalli, K. Kummer, M. Le Tacon, X. J. Zhou, N. B. Brookes, L. Braicovich, and G. Ghiringhelli
The already overcrowded phase diagram of cuprate superconductors has recently accommodated a region characterized by incommensurate charge density waves (CDW), partly overlapping with superconductivity, and included in the pseudogap regime. Although charge order is strengthened by high magnetic fields and competes with superconductivity, its role in Cooper pairing is still unassessed, calling for more complete characterization in different families of cuprates. The authors present an extensive x-ray scattering study of charge order in single layer La-doped Bi2201, and they show it extends up to optimal-doping (OP33K, $p$=0.16) in this family too. The CDW peak sharpens at ${T}_{c}$ and disappears above the pseudogap onset at temperature ${T}^{*}$. They also demonstrate that in the underdoped sample (OD15K, $p$=0.115) the charge density wave has no out-of-plane correlation and has dominant unidirectional nature within the planes.
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[Phys. Rev. B 94, 184511] Published Mon Nov 28, 2016
Small-scale universality of particle dynamics in quantum turbulence
2016-11-28T10:00:00-05:00
Author(s): M. La Mantia, P. Švančara, D. Duda, and L. Skrbek
We show that, in turbulent two-fluid flows of superfluid ^{4}He, the statistically described dynamics of small particles suspended in the liquid does not depend on the type of imposed flow, at scales smaller than the average distance between quantized vortices, the quantum length scale of the flow. …
[Phys. Rev. B 94, 184512] Published Mon Nov 28, 2016
Phase diagram of Eu magnetic ordering in Sn-flux-grown Eu(Fe_{1−x} Co_{x} )_{2} As_{2} single crystals
2016-11-28T10:00:00-05:00
Author(s): W. T. Jin, Y. Xiao, Z. Bukowski, Y. Su, S. Nandi, A. P. Sazonov, M. Meven, O. Zaharko, S. Demirdis, K. Nemkovski, K. Schmalzl, Lan Maria Tran, Z. Guguchia, E. Feng, Z. Fu, and Th. Brückel
The magnetic ground state of the Eu^{2+} moments in a series of Eu(Fe_{1−x}Co_{x})_{2}As_{2} single crystals grown from the Sn flux has been investigated in detail by neutron diffraction measurements. Combined with the results from the macroscopic properties (resistivity, magnetic susceptibility and…
[Phys. Rev. B 94, 184513] Published Mon Nov 28, 2016
Combined resistivity and Hall effect study on NaFe_{1−x} Rh_{x} As single crystals
2016-11-28T10:00:00-05:00
Author(s): Frank Steckel, Federico Caglieris, Robert Beck, Maria Roslova, Dirk Bombor, Igor Morozov, Sabine Wurmehl, Bernd Büchner, and Christian Hess
Electrical transport measurements are used to study the Rh-doped NaFeAs superconductor series with a focus on the tetragonal phase. The resistivity curvature has an anomalous temperature dependence evidencing in the phase diagram two crossover regions of changes in the scattering rate, the effective…
[Phys. Rev. B 94, 184514] Published Mon Nov 28, 2016
Intermediate regime between metal and superconductor below T=100 K in NiSi
2016-11-28T10:00:00-05:00
Author(s): Ashutosh Dahal, Jagath Gunasekera, Leland Harriger, S. H. Lee, Y. S. Hor, David J. Singh, and Deepak K. Singh
Magnetic response of a metal to an external magnetic field remains independent of the frequency of an ac magnetic field as temperature is reduced. Here, we report the discovery of an anomalous but enormous enhancement of the ac frequency dependent diamagnetic susceptibility below T≃100 K in metallic…
[Phys. Rev. B 94, 184516] Published Mon Nov 28, 2016
Weyl fermions with arbitrary monopoles in magnetic fields: Landau levels, longitudinal magnetotransport, and density-wave ordering
2016-11-28T10:00:00-05:00
Author(s): Xiao Li, Bitan Roy, and S. Das Sarma
We theoretically address the effects of strong magnetic fields in three-dimensional Weyl semimetals (WSMs) built out of Weyl nodes with a monopole charge n. For n=1, 2, and 3 we realize single, double, and triple WSM, respectively, and the monopole charge n determines the integer topological invaria…
[Phys. Rev. B 94, 195144] Published Mon Nov 28, 2016
Electron and hole doping in the relativistic Mott insulator Sr_{2} IrO_{4} : A first-principles study using band unfolding technique
2016-11-28T10:00:00-05:00
Author(s): Peitao Liu, Michele Reticcioli, Bongjae Kim, Alessandra Continenza, Georg Kresse, D. D. Sarma, Xing-Qiu Chen, and Cesare Franchini
We study the effects of dilute La and Rh substitutional doping on the electronic structure of the relativistic Mott insulator Sr_{2}IrO_{4} using fully relativistic and magnetically noncollinear density functional theory with the inclusion of an on-site Hubbard U. To model doping effects, we have ad…
[Phys. Rev. B 94, 195145] Published Mon Nov 28, 2016
Forces for structural optimizations in correlated materials within a DFT+embedded DMFT functional approach
2016-11-28T10:00:00-05:00
Author(s): Kristjan Haule and Gheorghe L. Pascut
We implemented the derivative of the free energy functional with respect to the atom displacements, so called force, within the combination of density functional theory and the embedded dynamical mean-field theory. We show that in combination with the numerically exact quantum Monte Carlo (MC) impur…
[Phys. Rev. B 94, 195146] Published Mon Nov 28, 2016
Nonrigid band shift and nonmonotonic electronic structure changes upon doping in the normal state of the pnictide high-temperature superconductor Ba(Fe_{1−x} Co_{x} )_{2} As_{2}
2016-11-28T10:00:00-05:00
Author(s): Paolo Vilmercati, Sung-Kwan Mo, Alexei Fedorov, Michael A. McGuire, Athena Sefat, Brian Sales, David Mandrus, David J. Singh, Wei Ku, Steve Johnston, and Norman Mannella
We report systematic angle-resolved photoemission (ARPES) experiments using different photon polarizations and experimental geometries and find that the doping evolution of the normal state of Ba(Fe_{1−x}Co_{x})_{2}As_{2} deviates significantly from the predictions of a rigid band model. The data re…
[Phys. Rev. B 94, 195147] Published Mon Nov 28, 2016
Field-induced suppression of charge density wave in GdNiC_{2}
2016-11-28T10:00:00-05:00
Author(s): Kamil K. Kolincio, Karolina Górnicka, Michał J. Winiarski, Judyta Strychalska-Nowak, and Tomasz Klimczuk
We report the specific heat, magnetic, magnetotransport, and galvanomagnetic properties of polycrystalline GdNiC_{2}. In the intermediate temperature region above T_{N}=20K, we observe large negative magnetoresistance due to Zeeman splitting of the electronic bands and partial destruction of a charg…
[Phys. Rev. B 94, 195149] Published Mon Nov 28, 2016
The “parity” anomaly on an unorientable manifold
2016-11-28T10:00:00-05:00
Author(s): Edward Witten
The “parity” anomaly is a potential violation of time-reversal and reflection symmetry that can occur for relativistic fermions coupled to gauge fields and/or gravity in 2+1 dimensional spacetime. It has played a role in condensed matter physics since the work of Haldane and others in the 1980’s. Only recently, as a result of developments in the theory of topological superconductors, has it been understood that the extension of this anomaly to an unorientable spacetime is significant. In the present paper, a systematic description is given of the “parity” anomaly on an unorientable spacetime. This is used to get a fuller understanding of gapped symmetry-preserving boundary states of a topological superconductor and to resolve some questions about the world-volume path integral of M-theory membranes.
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[Phys. Rev. B 94, 195150] Published Mon Nov 28, 2016
Renormalized parameters and perturbation theory in dynamical mean-field theory for the Hubbard model
2016-11-28T10:00:00-05:00
Author(s): A. C. Hewson
We calculate the renormalized parameters for the quasiparticles and their interactions for the Hubbard model in the paramagnetic phase as deduced from the low-energy Fermi-liquid fixed point using the results of a numerical renormalization-group calculation (NRG) and dynamical mean-field theory (DMF…
[Phys. Rev. B 94, 195152] Published Mon Nov 28, 2016
Optical transitions from the lowest to higher exciton and biexciton Rydberg states in CuCl
2016-11-28T10:00:00-05:00
Author(s): K. Miyajima, K. Sakaniwa, and M. Sugawara
We measured the optical transitions due to the internal energy levels of an exciton and biexciton in a CuCl single crystal using pump-probe spectroscopy. The transient absorption bands due to the transitions from the 1s to 2p and from the 1s to 3p exciton states were observed at 3 K, which is consis…
[Phys. Rev. B 94, 195209] Published Mon Nov 28, 2016
Vanadium interactions in crystalline silicon
2016-11-28T10:00:00-05:00
Author(s): D. J. Backlund, T. M. Gibbons, and S. K. Estreicher
The properties of interstitial vanadium (V_{i}) in Si and its interactions with the vacancy and the self-interstitial, as well as with hydrogen, are calculated using first-principles techniques. The stable configurations, gap levels, and binding energies agree well with the available experimental da…
[Phys. Rev. B 94, 195210] Published Mon Nov 28, 2016
Reversible devitrification in amorphous As_{2} Se_{3} under pressure
2016-11-28T10:00:00-05:00
Author(s): Azkar Saeed Ahmad, Hong-Bo Lou, Chuan-Long Lin, Ai-Guo Li, Ke Yang, K. Glazyrin, H. P. Liermann, Hermann Franz, Kenny Ståhl, Shuo Cui, Bruno Bureau, Dong-Xian Zhang, Xiao-Dong Wang, Qing-Ping Cao, A. Lindsay Greer, and Jian-Zhong Jiang
In pressure-induced reversible structural transitions, the term “reversible” refers to the recovery of the virgin structure in a material upon complete decompression. Pressure-induced amorphous-to-crystalline transitions have been claimed to be reversible, but evidence that amorphous material recove…
[Phys. Rev. B 94, 195211] Published Mon Nov 28, 2016
Photocarrier transport dynamics in InAs/GaAs quantum dot superlattice solar cells using time-of-flight spectroscopy
2016-11-28T10:00:00-05:00
Author(s): T. Tanibuchi, T. Kada, S. Asahi, D. Watanabe, T. Kaizu, Y. Harada, and T. Kita
We studied time-resolved photocarrier transport through InAs/GaAs quantum dot superlattice (QDSL) solar cells (SCs) using time-of-flight spectroscopy with an optical probe QD structure beneath the QDSL. Carriers optically pumped in the top p-GaAs layer were transported through the intrinsic layer, i…
[Phys. Rev. B 94, 195313] Published Mon Nov 28, 2016
Role of π−d hybridization in a 300-K organic-magnetic interface: Metal-free phthalocyanine single molecules on a bcc Fe(001) whisker
2016-11-28T10:00:00-05:00
Author(s): T. K. Yamada, Y. Yamagishi, S. Nakashima, Y. Kitaoka, and K. Nakamura
The realization of single molecular electronics is considered the next frontier to addressing and sustaining the storage needs of the future. In order to realize a single molecular device working at 300 K, two conditions must be satisfied: first, there must be no molecular diffusion, i.e., robust bo…
[Phys. Rev. B 94, 195437] Published Mon Nov 28, 2016
Pumping electrons in graphene to the M point in the Brillouin zone: Emergence of anisotropic plasmons
2016-11-28T10:00:00-05:00
Author(s): A. J. Chaves, N. M. R. Peres, and Tony Low
We consider the existence of plasmons in a nonequilibrium situation where electrons from the valence band of graphene are pumped to states in the Brillouin zone around the M point by a high intensity UV electromagnetic field. The resulting out-of-equilibrium electron gas is later probed by a weak el…
[Phys. Rev. B 94, 195438] Published Mon Nov 28, 2016
Graphene pn junction in a quantizing magnetic field: Conductance at intermediate disorder strength
2016-11-28T10:00:00-05:00
Author(s): Christian Fräßdorf, Luka Trifunovic, Nils Bogdanoff, and Piet W. Brouwer
In a graphene pn junction at high magnetic field, unidirectional “snake states” are formed at the pn interface. In a clean pn junction, each snake state exists in one of the valleys of the graphene band structure, and the conductance of the junction as a whole is determined by microscopic details of…
[Phys. Rev. B 94, 195439] Published Mon Nov 28, 2016
Nonlinear damping and dephasing in nanomechanical systems
2016-11-28T10:00:00-05:00
Author(s): Juan Atalaya, Thomas W. Kenny, M. L. Roukes, and M. I. Dykman
We present a microscopic theory of nonlinear damping and dephasing of low-frequency eigenmodes in nanomechanical and micromechanical systems. The mechanism of the both effects is scattering of thermally excited vibrational modes off the considered eigenmode. The scattering is accompanied by energy t…
[Phys. Rev. B 94, 195440] Published Mon Nov 28, 2016