2017-02-20There is growing evidence for the kinetics of homogeneous nucleation being a multi-step process. Colloid experiments and simulations now suggest that heterogeneous nucleation is no exception.
2017-02-13The spectroscopic observations of the very early stages of a supernova provide a glimpse into its environment prior to the explosion.
2017-02-13A recent burst of activity in applying machine learning to tackle fundamental questions in physics suggests that associated techniques may soon become as common in physics as numerical simulations or calculus.
2016-12-19Striking visualization of the flows generated by starfish larvae in their fluid environment offers unique insight into how these organisms live. The beautiful vortices they create betray a dynamic mechanism for trading swimming off against feeding.
2016-12-12Early forms of life could have started by molecular compounds coming together under conditions dense enough to promote reactions. But how might these droplets have undergone what we now know as cell division? The answer may be simpler than we think.
2016-12-05Ensembles of magnetic colloids can undergo an instability triggering the formation of clusters that move faster than the particles themselves. The many-body process relies on hydrodynamics alone and may prove useful for load delivery in fluidics.
2016-10-17Cold collisions between hydrogen molecules and helium atoms reveal how the change from spherical to non-spherical symmetry creates a quantum scattering resonance.
2016-04-25Radiation pressure noise from squeezed light constrains the precision of sensing devices such as improved gravitational wave interferometers.
2016-04-18The topological degeneracy associated with Majorana edge states has been measured in a spin-1/2 chain of cobalt atoms, thereby opening new avenues in low-dimensional quantum magnetism.
2017-03-20Signatures of spin–momentum-locked gap states in nanowire quantum point contacts that have all-electrical origin could provide the conditions for the quasiparticle excitations required for topological quantum computing.
2017-03-13The spatial separation of charge and spin densities in one-dimensional electron systems is the hallmark of Tomonaga–Luttinger physics. Waveform measurements now provide direct evidence for spin–charge separation.
2017-03-13When the entropy of a system scales as a function of its surface area, rather than its volume, it is said to obey an entropy area law. Now, an area law is shown to exist numerically in the entanglement entropy of superfluid helium.
2017-03-13With the help of a quantum simulator and Bayesian inference it is possible to determine the unknown Hamiltonian of a quantum system. An experiment demonstrates this using a photonic quantum simulator and a solid-state system.
2017-03-06Single photons stored in the collective Rydberg excitations of two atomic ensembles can interact with each other despite being micrometres apart.
2017-03-06Electrical rectification is usually achieved by layering p-type and n-type materials, but experiments now demonstrate rectification in a bulk polar semiconductor that has inversion-symmetry breaking and strong Rashba spin–orbit coupling.
2017-02-27An excited two-level system emits a single photon, but in special circumstances it can emit two. The reason for this unexpected two-photon emission lies with modified Rabi oscillations.
2017-02-27Using two entangled optical beams and post-selection, a single photon can have the same effect as eight photons in terms of the induced phase shift. This example illustrates the power of the so-called weak-value amplification.
2017-02-27The Berry curvature is essential to the study of the topological properties of a system, be it solid-state, atomic or photonic. In 1D photonic lattices there is a new clever way of measuring the Berry curvature.
2017-02-20Larmor coupling is a collisionless momentum exchange mechanism believed to occur in various astrophysical and space-plasma environments. The phenomenon is now observed in a laboratory experiment.
2017-02-13The success of machine learning techniques in handling big data sets proves ideal for classifying condensed-matter phases and phase transitions. The technique is even amenable to detecting non-trivial states lacking in conventional order.
2017-02-13A neural-network technique can exploit the power of machine learning to mine the exponentially large data sets characterizing the state space of condensed-matter systems. Topological transitions and many-body localization are first on the list.
2017-02-06A demonstration of switching between solitons of different chirality in a one-dimensional electronic system shows how topological excitations can be used to realize non-trivial algebraic operations.
2017-02-06A detailed analysis of low-temperature torsional oscillation measurements on two-dimensional 4He reveals evidence for intertwined superfluid and density wave order in this system.
2017-01-30Experiments show how domain walls can act as reservoirs of exchange energy that can be used to controllably launch or detect spin waves in ferromagnetic nanowires.
2017-01-23A laboratory study of turbulent flows reproduces the properties of jets in the atmospheres of gas giants, providing a better understanding of how these jets could extend deep into the planetary atmosphere.
2017-01-16Plasma optics enables the manipulation of highly intense laser beams. Now, plasma holograms, involving the creation of a modulated plasma surface on a solid target, are reported—for example, plasma hologram fork gratings produce optical vortices.
2017-01-09Unlike the usual picture of Anderson localization, in three-dimensional quasicrystals light waves can localize without disorder, thanks to their short mean free path.
2016-12-26Valleytronics — exploiting a system’s pseudospin degree of freedom — is being increasingly explored in sonic crystals. Now, valley transport of sound is reported for a macroscopic triangular-lattice array of rod-like scatterers in a 2D air waveguide.
2016-12-19Larval starfish use an outer layer of cilia to generate vortices in the fluid around their bodies. Spectacular imaging and mathematical modelling are combined to reveal that these dynamics are alternately optimized for swimming and feeding.
2016-12-19Photoemission is usually driven by the energy of the illuminating laser pulses, but in the strong-field regime, the photoemission from an array of plasmonic nanoparticles is shown to be controlled by the light’s electric field.
2016-12-12Resonances in the tunnelling spectra of a two-dimensional electron system provide strong evidence that the electrons arrange themselves into a Wigner crystal lattice with long-range ordering.
2016-12-05Collections of rolling colloids are shown to pinch off into motile clusters resembling droplets sliding down a windshield. These stable dynamic structures are formed through a fingering instability that relies on hydrodynamic interactions alone.
2016-12-05An optical second-harmonic generation study of a series of transition metal monopnictide Weyl semimetals reveals a giant, anisotropic nonlinear optical response in these systems.
2016-11-28Engineering moiré superlattices by stacking two-dimensional crystals could enable lateral superstructures to be formed where the local topological phase is periodically modulated, creating topological mosaics that are electrically switchable.
2016-11-28Adiabatic processes are useful in quantum control, but they are slow. A way around this is to exploit shortcuts to adiabaticity, which can speed things up — for instance, by boosting stimulated Raman adiabatic passage.
2016-11-21High-harmonic generation in a solid turns out to be sensitive to the interatomic bonding — a very useful feature that could enable the all-optical imaging of the interatomic potential.
2017-03-20Understanding the recombination dynamics in quantum dots is crucial for their use in optoelectronic devices. A photocurrent spectroscopy study shows how two distinct relaxation mechanisms are at play over different timescales.
2017-03-20Three-dimensional laser-written waveguide arrays are used to demonstrate type-II Weyl points, along with Fermi arc-like surface states, for light at optical wavelengths.
2017-02-27A torque magnetometry study of the pyrochlore iridate Eu2Ir2O7 reveals an unusual symmetry-breaking effect that persists above the Néel temperature of this antiferromagnet.
2017-02-20Controlled crystal growth can be achieved by initiating nucleation on a substrate — but the mechanisms at play are still poorly understood. Experiments and simulations now reveal conditions for the growth of defect-free crystals of charged colloids.
2017-02-20Controlling electric currents on the atomic scale requires being able to handle the ultrafast timescales involved. Now, experiments have demonstrated the feasibility of terahertz scanning tunnelling microscopy as a method for doing just that.
2017-02-13Controlled wave propagation in disordered media is a challenge because of scattering processes. Now it is shown that for speckled targets much larger than the wavelength, long-range correlations between the speckles enhance wave propagation control.
2017-02-13Type II supernova explosions are common, but our understanding of such events is not complete. Such an event was observed just three hours after the explosion started, providing important information about the early stages.
2017-02-06Lattice gauge theories are notoriously hard to analyse at finite fermion density, due to the so-called fermion sign problem. A study now shows this can be circumvented for the case of Ising gauge theories.
2017-02-06An experimental and theoretical study of the real-time dynamics in strong-field ionization of xenon atoms reveals the previously unknown role of transient ground-state polarization.
2017-01-30CP violation has deep implications for particle physics and cosmology. Previously observed only in meson decays, signs of CP violation have now been spotted in baryon decays by analysing the proton–proton collision data from the LHCb detector.
2017-01-30Many-body localization, which exhibits a fascinating interplay between disorder and interactions, can be studied using ultracold atoms in a quasiperiodic chain. Adding periodic driving makes things even more interesting.
2017-01-30Recent developments in advanced light sources have made it possible to transiently alter the electronic properties of materials by exciting specific atomic vibrations in solids. This study provides a theoretical framework for these experiments.
2017-01-23Classical light is as good as quantum light to characterize a quantum channel. This unexpected result has practical consequences that make an experimentalist’s life easier in some situations.
2017-01-23Two challenging questions related to the quantum Hall effect (QHE) are how edge reconstruction works and where the current flows. A new model now gives the answer for two types of QHE states — two separate downstream chiral edge channels are involved.
2017-01-16Combining synthetic magnetism and controlled dissipation, researchers created an optomechanical device in which photons and phonons are coupled, enabling non-reciprocal (asymmetric) photon transport and directional amplification.
2016-12-12Droplets are an appealing picture for protocells in origin-of-life studies, but it’s unclear how they would have propagated by growth and division. Theory suggests that chemically active droplets spontaneously split into equal daughter droplets.
2016-11-28Single atoms on a surface can be useful in spintronics applications, but their spin lifetime is limited by relaxation. By cleverly employing an STM tip, one can probe the spin dynamics and disentangle different effects leading to relaxation.