A solar cell is a photovoltaic device that converts solar radiation energy to electrical energy, which plays a leading role in alleviating global energy shortages and decreasing air pollution levels typical of conventional fossil fuels. To render solar cells more efficient, high visible-light absorption rates and excellent carrier transport properties are required to generate high carrier levels and

The present study carries out systematic thermodynamics analysis of Grain Boundary (GB) segregation and relaxation in Nano-Grained (NG) polycrystalline alloys. GB segregation and relaxation is an internal process towards thermodynamic equilibrium, which occurs naturally in NG alloys without any applied loads, causes deformation and generates internal stresses. The analysis comprehensively investigates

Magnetic skyrmion tubes and bobbers are two types of different nanoscale spin configurations that can coexist in nanostructures of chiral magnets. They are then proposed to be utilized as binary bits to build racetrack memory devices. The ability to manipulate the two magnetic objects controllably by current in nanostructures is the prerequisite to realize the device. Here, we demonstrate by numerical

In classical machine learning, a set of weak classifiers can be adaptively combined for improving the overall performance, a technique called adaptive boosting (or AdaBoost). However, constructing a combined classifier for a large data set is typically resource consuming. Here we propose a quantum extension of AdaBoost, demonstrating a quantum algorithm that can output the optimal strong classifier

We report thermodynamic and neutron diffraction measurements on the magnetic ordering properties of the honeycomb lattice magnet YbCl3. We find YbCl3 exhibits a Néel type long-range magnetic order at the wavevector (0, 0, 0) below TN = 600 mK. This magnetic order is associated with a small sharp peak in heat capacity and most magnetic entropy release occurs above the magnetic ordering temperature.

The meridional circulation of the Sun, which is observed to be poleward at the surface, should have a return flow at some depth. Since large-scale flows like the differential rotation and the meridional circulation are driven by turbulent stresses in the convection zone, these flows are expected to remain confined within this zone. Current observational (based on helioseismology) and theoretical (based

In this work, we systematically studied the magnetic and transport properties of EuAg4As2 single crystals. It was found that the two antiferromagnetic transitions (TN1 = 10 K and TN2=15 K) were driven to lower temperatures by an applied magnetic field. Below TN1, two successive metamagnetic transitions were observed when a magnetic field was applied in the ab plane (H//ab-plane). For both H//ab and

Stimulated adiabatic passage has been extensively studied to achieve robust and selective population transfer in quantum systems. Recently, the quantum-classic analogy has been rapidly developing and can be considered responsible for the implementation of the adiabatic transfer of sound energy in cavity chain systems. In this article, we investigate the adiabatic transfer of sound energy between two

Surface instability of compliant film/substrate bilayers has raised considerable interests due to its broad applications such as wrinkle-driven surface renewal and antifouling, shape-morphing for camouflaging skins, and micro/nano-scale surface patterning control. However, it is still a challenge to precisely predict and continuously trace secondary bifurcation transitions in the nonlinear post-buckling

The three-body problem can be traced back to Newton in 1687, but it is still an open question today. Note that only a few periodic orbits of three-body systems were found in 300 years after Newton mentioned this famous problem. Although triple systems are common in astronomy, practically all observed periodic triple systems are hierarchical (similar to the Sun, Earth and Moon). It has traditionally

We make a full classification of scalar monomials built of the Riemann curvature tensor up to the quadratic order and of the covariant derivatives of the scalar field up to the third order. From the point of view of the effective field theory, the third or even higher order covariant derivatives of the scalar field are of the same importance as the higher curvature terms, and thus should be taken into

The energy level separation between the edge states in topological insulator quantum dots lies in the terahertz (THz) range. Quantum confinement ensures the nonuniformity of the energy level separation near the Dirac point. Based on these features, we propose that a topological insulator quantum dot array can be operated as an electrically pumped continuous-wave THz laser. The proposed device can operate

We report the crystal structures and physical properties of trilayer nickelates Nd4Ni3O10 and Nd4Ni3O8. Measurements of magnetization and electrical resistivity display contrasting behaviors in the two compounds. Nd4Ni3O10 shows a paramagnetic metallic behavior with a metal-to-metal phase transition (T*) at about 162 K, as revealed by both magnetic susceptibility and resistivity. Further magnetoresistance

Lithium niobate on insulator (LNOI) provides a platform for the fundamental physics investigations and practical applications of integrated photonics. However, as an indispensable building block of integrated photonics, lasers are in short supply. In this paper, erbium-doped LNOI laser in the 1550-nm band was demonstrated in microdisk cavities with high quality factors fabricated in batches by UV exposure

We propose a refined version of trans-Planckian censorship conjecture (TCC), which could be elaborated from the strong scalar weak gravity conjecture combined with some entropy bounds. In particular, no fine-tuning on the inflation model-building is required in the refined TCC, and it automatically passes the tests from those stringy examples that support the original TCC. Furthermore, our refined

The commercialization of lithium niobate on insulator (LNOI) wafer has resulted in significant on-chip photonic integration application owing to its remarkable photonic, acousto-optic, electro-optic, and piezoelectric nature. In recent years, a variety of high-performance on-chip LNOI-based photonic devices have been realized. In this study, we developed a 1-mol% erbium-doped lithium niobate crystal

Neutral triple gauge couplings (nTGCs) are absent in the standard model effective theory up to dimension-6 operators, but could arise from dimension-8 effective operators. In this work, we study the pure gauge operators of dimension-8 that contribute to nTGCs and are independent of the dimension-8 operator involving the Higgs doublet. We show that the pure gauge operators generate both ZγZ* and Zγγ*

Water is a fascinating material. Its composition is simple—one oxygen and two hydrogen atoms—but its chemistry and physics are extremely complex and exhibit 75 documented anomalies. Although these anomalies and their molecular origin are not completely understood, we know that hydrogen bonds play key roles in all of the phases of water. Moreover, there is experimental evidence that the polymorphism

Materials failure under some sort of loading is a well-known natural phenomenon, and the reliable prediction of materials failure is the most important key issue for many different kinds of engineering structures based on their safety considerations. In this research, instead of establishing empirical models, the material failure process was modeled as a nonequilibrium process based on the microstructural

We analytically study the electronic structure and optical properties of zigzag-edged phosphorene nanoribbons (ZPNRs) using the tight-binding Hamiltonian and Kubo formula. By directly solving the discrete Schrodinger equation, we obtain the energy spectra and wavefunctions for N-ZPNR (where TV is the number of transverse zigzag atomic chains) and classify the eigenstates according to the lattice symmetry

Multiparty quantum communication ensures information-theoretic security for transmitting private information among multiuser networks. In principle, measurement-device-independent (MDI) techniques can close all detection loopholes while usually utilizing large amounts of quantum resources in basis reconciliation. We propose a three-party MDI quantum secret sharing (QSS) protocol that is secure against

Studies have shown that the use of pulsar timing arrays (PTAs) is among the approaches with the highest potential to detect very low-frequency gravitational waves in the near future. Although the capture of gravitational waves (GWs) by PTAs has not been reported yet, many related theoretical studies and some meaningful detection limits have been reported. In this study, we focused on the nanohertz

The powerlaw X-ray spectra of active galactic nuclei at moderate to high accretion rates normally appear softer when they brighten, for which the underlying mechanisms are yet unclear. Utilizing XMM-Newton observations and excluding photons < 2 keV to avoid contamination from the soft excess, in this work we scrutinize the powerlaw spectral variability of NCG 4051 from two new aspects. We first find

We propose a light-weight deep convolutional neural network (CNN) to estimate the cosmological parameters from simulated 3-dimensional dark matter distributions with high accuracy. The training set is based on 465 realizations of a cubic box with a side length of 256 h−1 Mpc, sampled with 1283 particles interpolated over a cubic grid of 1283 voxels. These volumes have cosmological parameters varying

The Tianlai Cylinder Pathfinder is a radio interferometer array designed to test techniques for 21 cm intensity mapping in the post-reionization Universe, with the ultimate aim of mapping the large scale structure and measuring cosmological parameters such as the dark energy equation of state. Each of its three parallel cylinder reflectors is oriented in the north-south direction, and the array has

The long-range interaction between Rydberg-excited atoms endows a medium with large optical nonlinearity. Here, we demonstrate an optical switch to operate on a single photon from an entangled photon pair under a Rydberg electromagnetically induced transparency configuration. With the presence of the Rydberg blockade effect, we switch on a gate field to make the atomic medium nontransparent thereby

The search for high energy density materials (HEDMs) in polymeric nitrogen compounds has gained considerable attention. Previous theoretical predictions and experiments have revealed that metal ions can be used to stabilize the pentazolate (N −5 ) anion. In this work, by employing a machine learning-accelerated crystal structure searching method and first-principles calculations, we found that the

Evaporation of aqueous polystyrene (PS) nanoparticles droplets on silicon and polydimethylsiloxane (PDMS) surfaces was studied. Experimental results showed that softer PDMS surfaces yielded a longer constant contact radius (CCR) stage, which could be ascribed to surface deformation of PDMS induced by the vertical component of liquid-vapor interfacial tension. Ringlike depositions of nanoparticles with

Formation of the Hβ λ4861.34 Å line is an important topic related to the diagnosis of the basic configuration of magnetic fields in the solar and stellar chromospheres. Specifically, broadening of the Hβ λ4861.34 Å line occurs due to the magnetic and micro-electric fields in the solar atmosphere. The formation of Hβ in the model umbral atmosphere is presented based on the assumption of non-local thermodynamic

Quantum secure direct communication (QSDC) transmits information directly over a quantum channel. In addition to security in transmission, it avoids loopholes of key loss and prevents the eavesdropper from getting ciphertext. In this article, we propose a QSDC protocol using entangled photon pairs. This protocol differs from existing entanglement-based QSDC protocols because it does not perform Bell-state

We report a comprehensive neutron scattering study on the spin excitations in the magnetic Weyl semimetal Co3Sn2S2 with a quasi-two-dimensional structure. Both in-plane and out-of-plane dispersions of the spin waves were revealed in the ferromagnetic state. Similarly, dispersive but damped spin excitations were found in the paramagnetic state. The effective exchange interactions were estimated using

The generation and manipulation of strong entanglement and Einstein-Podolsky-Rosen (EPR) steering in macroscopic systems are outstanding challenges in modern physics. Especially, the observation of asymmetric EPR steering is important for both its fundamental role in interpreting the nature of quantum mechanics and its application as resource for the tasks where the levels of trust at different parties

A new quantum spin liquid (QSL) candidate material H3LiIr2O6 was synthesized recently and was found not to show any magnetic order or phase transition down to low temperatures. In this work, we study the quantum dynamics of the hydrogen ions, i.e., protons, in this material by combining first-principles calculations and theoretical analysis. We show that each proton and its adjacent oxygen ions form

We investigate the implication of trans-Planckian censorship conjecture (TCC) for the initial state of primordial perturbations. It is possible to set the state of perturbation modes in the infinite past as the Minkowski vacuum, only if the pre-inflationary era is past-complete. We calculate the evolution of the perturbation modes in such a pre-inflationary era and show that at the beginning of inflation

LaIrIn5 is a reference compound of the heavy-fermion superconductor CeIrIn5. The lack of f electrons in LaIrIn5 indicates that there should not be any f electron participating in the construction of its Fermi surface. Thus the electronic structure comparison between LaIrIn5 and CeIrIn5 provides a good platform to study the properties of f electrons. Here angle-resolved photoemission spectroscopy (ARPES)

Nonreciprocal directional dichroism in multiferroics, namely magnetoelectric coupling in the dynamic regime, is endowed with rich physics and promising applications, which are entangled with fundamental physical components, such as spin, orbital, lattice, charge, and topology. Such a linear nonreciprocal response behavior in the GHz-THz frequency range, represented by optical magnetoelectric effect

It has been over 30 years since the concept of optical vortices was first proposed by Coullet et al. in 1989, and the field of structured beams has grown extremely. In the last two decades, partially coherent vortex beams (PCVBs) have received increasing interest in the fields of optical manipulation, optical communication, optical imaging, etc., and great progress has been made in the area of the

Single crystals subjected to shock compression exhibit responses with distinct two-wave structures for certain crystal orientations. However, little is known to date regarding how the shock response depends on crystal orientation, and especially why the two-wave structure depends on the crystal orientation. In this work, molecular dynamics simulations of shock compressions in copper single crystals

We propose a simple quasi-continuous monolayer graphene structure and achieve a dynamically tunable triple plasmon-induced transparency (PIT) effect in the proposed structure. Additional analyses indicate that the proposed structure contains a self-constructed bright-dark-dark mode system. A uniform theoretical model is introduced to investigate the spectral response characteristics and slow light-effects

In recent years, metasurfaces that enable the flexible wavefront modulation at sub-wavelength scale have been widely used into holographic display, due to its prominent advantages in polarization degrees of freedom, viewing angle, and achromaticity in comparison with traditional holographic devices. In holography, the computational complexity of hologram, imaging sharpness, energy utilization, reproduction

Monoclinic Ga2O3 (β-Ga2O3) is a promising material for achieving solar-blind photodetection because of its unique characteristics, including its high breakdown electric field, radiation hardness, thermal and chemical stabilities, and intrinsic visible/solar-blind properties. Until now, several studies have investigated the development of high-performance β-Ga2O3 solar-blind photodetectors. However

We provide a perspective review over the recent development of short-pulsed Raman fiber lasers (RFLs), which can provide laser emissions with flexible wavelengths for a variety of applications as well as an excellent platform to investigate various nonlinear pulse dynamics behaviors that cannot be captured in conventional rare-earth (RE) doped counterparts. Various pulse generation techniques have

The cooper pairs in the heavy-fermion superconductor CeCu2Si2 are formed of heavy fermions. Therefore, the heavy fermions are fundamental to the emergence of unconventional superconductivity and associated non-Fermi-liquid behavior in the normal state. The interplay between localization and itinerancy manifested on the electronic structure is key for understanding the heavyfermion behavior. Here, via

Applying a three-band model and the random phase approximation, we theoretically study the spin excitations in nickelate superconductors, which have been newly discovered. The spin excitations were found to be incommensurate in the low energy region. The spin resonance phenomenon emerged as the excitation energy increased. The intensity can be maximized at the incommensurate or commensurate momentum

Dynamo theory describes the magnetic field induced by the rotating, convecting and electrically conducting fluid in a celestial body. The classical ABC-flow model represents fast dynamo action, required to sustain such a magnetic field. In this letter, Lagrangian coherent structures (LCSs) in the ABC-flow are detected through Finite-time Lyapunov exponents (FTLE). The flow skeleton is identified by

Magnetic Weyl semimetals (WSMs) with broken time-reversal symmetry (TRS) hosting topological band structures are expected to provide an ideal platform for investigating topological superconductivity and spintronics. However, the experimental verification of magnetic WSMs is very challenging. Very recently, the kagome magnet Co3Sn2S2 was confirmed to be a magnetic WSM by both angle-resolved photoemission

Metasurfaces, which are planar arrays of subwavelength artificial structures, have emerged as excellent platforms for the integration and miniaturization of electromagnetic devices and provided ample possibilities for single-dimensional and multidimensional manipulations of electromagnetic waves. However, owing to the limited interactions between planar thin metallic nanostructures and electromagnetic

With its tremendous success in many machine learning and pattern recognition tasks, deep learning, as one type of data-driven models, has also led to many breakthroughs in other disciplines including physics, chemistry and material science. Nevertheless, the supremacy of deep learning over conventional optimization approaches heavily depends on the huge amount of data collected in advance to train

The study of topological semimetals hosting spin-1 Weyl points (WPs) beyond Dirac points and WPs has attracted a great deal of attention. However, a spin-1 Weyl semimetal that exclusively possesses spin-1 WPs in a clean frequency window without being shadowed by any other nodal points is yet to be discovered. This study reports a spin-1 Weyl semimetal in a phononic crystal. Its spin-1 WPs are touched

In this work, we study the local distinguishability of maximally entangled states (MESs). In particular, we are concerned with whether any fixed number of MESs can be locally distinguishable for sufficiently large dimensions. Fan and Tian et al. have already obtained two satisfactory results for the generalized Bell states (GBSs) and the qudit lattice states when applied to prime or prime power dimensions

In this work, by incorporating different electrodes (Ta/Ti) onto TaOx dielectric layer, we studied both the conductance reading and conductance updating (long term potentiation and depression) linearities in the two RRAM devices. Owing to the composition modulation (CM) mechanism, the Ta-electrode device shows better conductance reading and updating linearities. The RRAM device linearities directly

Efficient quantum circuits for arithmetic operations are vital for quantum algorithms. A fault-tolerant circuit is required for a robust quantum computing in the presence of noise. Quantum circuits based on Clifford+T gates are easily rendered fault-tolerant. Therefore, reducing the T-depth and T-Count without increasing the qubit number represents vital optimization goals for quantum circuits. In

Low-temperature specific heat (SH) is measured for the 12442-type KCa2Fe4As4F2 single crystal under different magnetic fields. A clear SH jump with the height of \(\Delta C/T|_{T_c}\) = 130 mJ moL−1 K−2 is observed at the superconducting transition temperature Tc. It is found that the electronic SH coefficient ∆γ(H) quickly increases when the field is in the low-field region below 3 T and then considerably

Using density functional calculations, we elucidate the interaction between magnons and phonons on Fe(001) and O/Fe(001) surfaces. The effective Heisenberg exchange parameters between neighbor sites (Ji) were derived by fitting the ab initio spin spiral dispersion relation to a classical Heisenberg model. In bulk Fe, J5b has a larger amplitude than J2b-J4b. Surface magnons were softer on the Fe(001)

We successfully fabricate high-entropy alloys and amorphous alloy composites by adopting the proposed ultrasonic vibration method. The low-stress, low-temperature method enables us to create composites that combine both amorphous and crystalline properties. Microscopic observations and computed tomography measurements indicate good bonding quality without pores or cracks in the composites. Due to the

In this work, HengYan Wang and Jian Pan contributed equally to this work. The annotation for the contribution was omitted in the original publication of this paper [1]. It can be conformed in the submitted PDF version of the manuscript. Hence, the sentence “HengYan Wang and Jian Pan contributed equally to this work.” should be added.

We theoretically investigate the optical second-order sideband generation (OSSG) in an optical parity-time (PT) symmetric system, which consists of a passive cavity trapping the atomic ensemble and an active cavity. Compared with the double-passive system, it is found that near the exceptional point (EP), the efficiency of the OSSG increases sharply not only for the blue probepump detuning resonant

Investigations into the phonon behavior provide important information on interactions between different excitations in quantum materials. We perform a detailed study of the phonon behavior in the topological insulator Sn-doped Bi1.1Sb0.9Te2S using infrared spectroscopy. We observe two IR-active phonon modes at about 64 and 165 cm−1, which are labeled with α and β, respectively. While the evolution

We report a comparative investigation of the topographic features and nanomechanical responses of surface nanobubbles, polymeric nanodrops, and solid microparticles submerged in water and probed by atomic force microscopy in different operating modes. We show that these microscopic objects exhibit similar topographies, either hemispherical or hemiellipsoidal, in the standard tapping mode, and thus

In this work, (-2 0 1) β-Ga2O3 films are grown on GaN substrate by metal organic chemical vapor deposition (MOCVD). It is revealed that the β-Ga2O3 film grown on GaN possesses superior crystal quality, material homogeneity and surface morphology than the results of common heteroepitaxial β-Ga2O3 film based on sapphire substrate. Further, the relevance between the crystal quality of epitaxial β-Ga2O3