Holographic reconstruction is troubled by the phase-conjugate wave front arising from Hermitian symmetry of the complex field. The so-called twin image obfuscates the reconstruction in solving the inverse problem. Here we quantitatively reveal how and how much the twin image affects the reconstruction and propose a compressive sensing (CS) approach to reconstruct a hologram completely free from the twin image. Using the canonical basis, the incoherence condition of CS is naturally satisfied by the Fourier transformation associated with wave propagation. With the propagation kernel function related to the distance, the object wave diffracts into a sharp pattern while the phase-conjugate wave diffracts into a diffuse pattern. An iterative algorithm using a total variation sparsity constraint could filter out the diffuse conjugated signal and overcome the inherent physical symmetry of holographic reconstruction. The feasibility is verified by simulation and experimental results, as well as a comparative study to an existing phase retrieval method.

Growing crystals form a cavity when placed against a wall. The birth of the cavity is observed both by optical microscopy of sodium chlorate crystals (${\mathrm{NaClO}}_3$) growing in the vicinity of a glass surface, and in simulations with a thin film model. The cavity appears when growth cannot be maintained in the center of the contact region due to an insufficient supply of growth units through the liquid film between the crystal and the wall. We obtain a nonequilibrium morphology diagram characterizing the conditions under which a cavity appears. Cavity formation is a generic phenomenon at the origin of the formation of growth rims observed in many experiments, and is a source of complexity for the morphology of growing crystals in natural environments. Our results also provide restrictions for the conditions under which compact crystals can grow in confinement.

We introduce two-dimensional topological insulators in proximity to high-temperature cuprate or iron-based superconductors as high-temperature platforms of Majorana Kramers pairs of zero modes. The proximity-induced pairing at the helical edge state of the topological insulator serves as a Dirac mass, whose sign changes at the sample corner because of the pairing symmetry of high-$T_c$ superconductors. This sign changing naturally creates at each corner a pair of Majorana zero modes protected by time-reversal symmetry. Conceptually, this is a topologically trivial superconductor-based approach for Majorana zero modes. We provide quantitative criteria and suggest candidate materials for this proposal.

We demonstrate that the nontrivial magnetic texture of antiferromagnetic Skyrmions (AFM Sks) promotes a nonvanishing topological spin Hall effect (TSHE) on the flowing electrons. This effect results in a substantial enhancement of the nonadiabatic torque and, hence, improves the Skyrmion mobility. This nonadiabatic torque increases when decreasing the Skyrmion size, and, therefore, scaling down results in a much higher torque efficiency. In clean AFM Sks, we find a significant boost of the TSHE close to the van Hove singularity. Interestingly, this effect is enhanced away from the band gap in the presence of nonmagnetic interstitial defects. Furthermore, unlike their ferromagnetic counterpart, the TSHE in AFM Sks increases with an increase in the disorder strength, thus opening promising avenues for materials engineering of this effect.

Engineering effective electronic parameters is a major focus in condensed matter physics. Their dynamical modulation opens the possibility of creating and controlling physical properties in systems driven out of equilibrium. In this Letter, we demonstrate that the Hubbard $U$, the widely used on-site Coulomb repulsion in strongly correlated materials, can be modified on femtosecond timescales by a strong nonresonant laser pulse excitation in the prototypical charge-transfer insulator NiO. Using our recently developed time-dependent density-functional theory plus self-consistent $U$ method, we demonstrate the importance of a dynamically modulated $U$ in the description of the high-harmonic generation of NiO. Our study opens the door to novel ways of modifying effective interactions in strongly correlated materials via laser driving, which may lead to new control paradigms for field-induced phase transitions and perhaps laser-induced Mott insulation in charge-transfer materials.

We study the topological properties of one-dimensional systems undergoing unitary time evolution. We show that symmetries possessed both by the initial wave function and by the Hamiltonian at all times may not be present in the time-dependent wave function—a phenomenon which we dub “dynamically induced symmetry breaking.” This leads to the possibility of a time-varying bulk index after quenching within noninteracting gapped topological phases. The consequences are observable experimentally through particle transport measurements. With reference to the entanglement spectrum, we explain how the topology of the wave function can change out of equilibrium, both for noninteracting fermions and for symmetry-protected topological phases protected by antiunitary symmetries.

We use gravitational-wave observations of the binary neutron star merger GW170817 to explore the tidal deformabilities and radii of neutron stars. We perform a Bayesian parameter estimation with the source location and distance informed by electromagnetic observations. We also assume that the two stars have the same equation of state; we demonstrate that, for stars with masses comparable to the component masses of GW170817, this is effectively implemented by assuming that the stars’ dimensionless tidal deformabilities are determined by the binary’s mass ratio $q$ by ${\mathrm{\Lambda }}_1/{\mathrm{\Lambda }}_2=q^6$. We investigate different choices of prior on the component masses of the neutron stars. We find that the tidal deformability and 90% credible interval is $\tilde{\mathrm{\Lambda }}={222}_{-138}^{+420}$ for a uniform component mass prior, $\tilde{\mathrm{\Lambda }}={245}_{-151}^{+453}$ for a component mass prior informed by radio observations of Galactic double neutron stars, and $\tilde{\mathrm{\Lambda }}={233}_{-144}^{+448}$ for a component mass prior informed by radio pulsars. We find a robust measurement of the common areal radius of the neutron stars across all mass priors of $8.9\le \widehat{R}\le 13.2\mathrm{km}$, with a mean value of $⟨\widehat{R}⟩=10.8\mathrm{km}$. Our results are the first measurement of tidal deformability with a physical constraint on the star’s equation of state and place the first lower bounds on the deformability and areal radii of neutron stars using gravitational waves.

The ${\chi }_{b1}(3P)$ and ${\chi }_{b2}(3P)$ states are observed through their $\mathrm{\Upsilon }(3S)\gamma$ decays, using an event sample of proton-proton collisions collected by the CMS experiment at the CERN LHC. The data were collected at a center-of-mass energy of 13 TeV and correspond to an integrated luminosity of $80.0{\mathrm{fb}}^{-1}$. The $\mathrm{\Upsilon }(3S)$ mesons are identified through their dimuon decay channel, while the low-energy photons are detected after converting to $e^{+}{e}^{-}$ pairs in the silicon tracker, leading to a ${\chi }_b(3P)$ mass resolution of 2.2 MeV. This is the first time that the $J=1$ and 2 states are well resolved and their masses individually measured: $10513.42\pm 0.41(\text{stat})\pm 0.18(\text{syst})\mathrm{MeV}$ and $10524.02\pm 0.57(\text{stat})\pm 0.18(\text{syst})\mathrm{MeV}$; they are determined with respect to the world-average value of the $\mathrm{\Upsilon }(3S)$ mass, which has an uncertainty of 0.5 MeV. The mass splitting is measured to be $10.60\pm 0.64(\text{stat})\pm 0.17(\text{syst})\mathrm{MeV}$.

We establish a localization phase diagram for light in a random three-dimensional (3D) ensemble of motionless two-level atoms with a threefold degenerate upper level, in a strong static magnetic field. Localized modes appear in a narrow spectral band when the number density of atoms $\rho$ exceeds a critical value ${\rho }_c\simeq 0.1k_0^3$, where $k_0$ is the wave number of light in the free space. A critical exponent of the localization transition taking place upon varying the frequency of light at a constant $\rho >{\rho }_c$ is estimated to be $\nu =1.57\pm 0.07$. This classifies the transition as an Anderson localization transition of 3D orthogonal universality class.

We realize a two-component dipolar Fermi gas with tunable interactions, using erbium atoms. Employing a lattice-protection technique, we selectively prepare deeply degenerate mixtures of the two lowest spin states and perform high-resolution Feshbach spectroscopy in an optical dipole trap. We identify a comparatively broad Feshbach resonance and map the interspin scattering length in its vicinity. The Fermi mixture shows a remarkable collisional stability in the strongly interacting regime, providing a first step towards studies of superfluid pairing, crossing from Cooper pairs to bound molecules, in presence of dipole-dipole interactions.

The archetypal two-impurity Kondo problem in a serially coupled double quantum dot is investigated in the presence of a thermal bias $\theta$. The slave-boson formulation is employed to obtain the nonlinear thermal and thermoelectrical responses. When the Kondo correlations prevail over the antiferromagnetic coupling $J$ between dot spins, we demonstrate that the setup shows negative differential thermal conductance regions behaving as a thermal diode. In addition, we report a sign reversal of the thermoelectric current $I(\theta )$ controlled by $t/\mathrm{\Gamma }$ ($t$ and $\mathrm{\Gamma }$ denote the interdot tunnel and reservoir-dot tunnel couplings, respectively) and $\theta$. All these features are attributed to the fact that at large $\theta$ both $Q(\theta )$ (heat current) and $I(\theta )$ are suppressed regardless of the value of $t/\mathrm{\Gamma }$ because the double dot decouples at high thermal biases. Finally, for a finite $J$, we investigate how the Kondo-to-antiferromagnetic crossover is altered by $\theta$.

Magnetism in topological insulators (TIs) opens a topologically nontrivial exchange band gap, providing an exciting platform for manipulating the topological order through an external magnetic field. Here, we show that the surface of an antiferromagnetic thin film can magnetize the top and the bottom TI surface states through interfacial couplings. During the magnetization reversal, intermediate spin configurations are ascribed from unsynchronized magnetic switchings. This unsynchronized switching develops antisymmetric magnetoresistance spikes during magnetization reversals, which might originate from a series of topological transitions. With the high Néel ordering temperature provided by the antiferromagnetic layers, the signature of the induced topological transition persists up to $\sim 90\mathrm{K}$.

A clear thermal Hall signal (${\kappa }_{xy}$) was observed in the spin-liquid phase of the $S=1/2$ kagome antiferromagnet Ca kapellasite $[{\mathrm{CaCu}}_3(\mathrm{OH}{)}_6{\mathrm{Cl}}_2·0.6{\mathrm{H}}_2\mathrm{O}]$. We found that ${\kappa }_{xy}$ is well reproduced, both qualitatively and quantitatively, using the Schwinger-boson mean-field theory with the Dzyaloshinskii-Moriya interaction of $D/J\sim 0.1$. In particular, ${\kappa }_{xy}$ values of Ca kapellasite and those of another kagome antiferromagnet, volborthite, converge to one single curve in simulations modeled using Schwinger bosons, indicating a common temperature dependence of ${\kappa }_{xy}$ for the spins of a kagome antiferromagnet.

We study the Rydberg exciton absorption of ${\mathrm{Cu}}_2\mathrm{O}$ in the presence of free carriers injected by above-band-gap illumination. Already at plasma densities ${\rho }_{\mathrm{EH}}$ below one hundredth electron-hole pair per $\mu {\mathrm{m}}^3$, exciton lines are bleached, starting from the highest observed principal quantum number, while their energies remain constant. Simultaneously, the band gap decreases by correlation effects with the plasma. An exciton line loses oscillator strength when the band gap approaches its energy, vanishing completely at the crossing point. Adapting a plasma-physics description, we describe the observations by an effective Bohr radius that increases with rising plasma density, reflecting the Coulomb interaction screening by the plasma.

We show that the community structure of a network can be used as a coarse version of its embedding in a hidden space with hyperbolic geometry. The finding emerges from a systematic analysis of several real-world and synthetic networks. We take advantage of the analogy for reinterpreting results originally obtained through network hyperbolic embedding in terms of community structure only. First, we show that the robustness of a multiplex network can be controlled by tuning the correlation between the community structures across different layers. Second, we deploy an efficient greedy protocol for network navigability that makes use of routing tables based on community structure.

We show that the fraction of time that a thermodynamic current spends above its average value follows the arcsine law, a prominent result obtained by Lévy for Brownian motion. Stochastic currents with long streaks above or below their average are much more likely than those that spend similar fractions of time above and below their average. Our result is confirmed with experimental data from a Brownian Carnot engine. We also conjecture that two other random times associated with currents obey the arcsine law: the time a current reaches its maximum value and the last time a current crosses its average value. These results apply to, inter alia, molecular motors, quantum dots, and colloidal systems.

Using a semianalytical approach based on the thin-shell approximation, we calculate the long-term evolution of supernova remnants (SNRs) while also accounting for the cosmic rays (CRs) accelerated at their blast waves. Our solution reproduces the results of state-of-the-art fluid simulations across the adiabatic and radiative stages for the gas-only case, and it predicts that typical CR acceleration efficiencies ($\approx 10\%$) can boost SNR momentum deposition by a factor of 2–3. This enhancement can become as large as an order of magnitude in environments in which the gas experiences more severe radiative losses. This result may have a crucial impact on modeling the effect of supernova feedback on star formation and galaxy evolution.

Jet substructure observables have significantly extended the search program for physics beyond the standard model at the Large Hadron Collider. The state-of-the-art tools have been motivated by theoretical calculations, but there has never been a direct comparison between data and calculations of jet substructure observables that are accurate beyond leading-logarithm approximation. Such observables are significant not only for probing the collinear regime of QCD that is largely unexplored at a hadron collider, but also for improving the understanding of jet substructure properties that are used in many studies at the Large Hadron Collider. This Letter documents a measurement of the first jet substructure quantity at a hadron collider to be calculated at next-to-next-to-leading-logarithm accuracy. The normalized, differential cross section is measured as a function of ${\log }_{10}{\rho }^2$, where $\rho$ is the ratio of the soft-drop mass to the ungroomed jet transverse momentum. This quantity is measured in dijet events from $32.9{\mathrm{fb}}^{-1}$ of $\sqrt{s}=13\mathrm{TeV}$ proton-proton collisions recorded by the ATLAS detector. The data are unfolded to correct for detector effects and compared to precise QCD calculations and leading-logarithm particle-level Monte Carlo simulations.