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Domain wall network:A dual solution for gravitational waves and Hubble tension?

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Science China(physics,Mechanics & Astronomy) 2024年第11期Mechanics & Astronomy) .卷 43-50页

作者： Ligong Bian Shuailiang Ge Changhong Li Jing Shu Junchao Zong department of physics and Chongqing Key Laboratory for Strongly Coupled physics Chongqing University Center for High Energy physics Peking University School of physics and State Key Laboratory of Nuclear physics and Technology Peking University department of Astronomy Key Laboratory of Astroparticle Physics of Yunnan Province School of Physics and AstronomyYunnan University Beijing Laser Acceleration Innovation Center department of physics Nanjing University CAS Key Laboratory of Theoretical physics Institute of Theoretical Physics Chinese Academy of Sciences

We explore the possibility that domain wall networks generate the stochastic gravitational wave background（SGWB） observed as a strong common power-law process in the Data Release-2 of Parkes Pulsar Timing Array. We find that a broad range of parameters, specifically wall tension around σDW～（29-414 TeV）3and wall-decay temperature within Td～ 20-257 MeV, can explain this phenomenon at a 68% credible level. Meanwhile, the same parameters could ease the Hubble tension if particles from these domain wall networks decay into dark radiation. We establish a direct analytical relationship, ?GW（fp, T0）h2～ ?radh2(?ν?Neff)2,to illustrate this coincidence, underlining its importance in the underlying physics and potential applicability to a wider range of models and data. Conversely, if the common power-law process is not attributed to domain wall networks, our findings impose tight limits on the wall tension and decay temperature.

关键词： domain wall gravitational waves Hubble tension

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Tidal effects based on a GUP-induced effective metric

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Communications in Theoretical physics 2024年第9期76卷 65-74页

作者： Soon-Tae Hong Yong-Wan Kim young-Jai Park Center for Quantum Spacetime and department of physics Sogang University department of physics and Research Institute of physics and Chemistry Jeonbuk National University department of physics Sogang University

In this paper, we study tidal forces in the Schwarzschild black hole, whose metric explicitly includes a generalized uncertainty principle(GUP) effect. We also investigate interesting features of the geodesic equations and tidal effects that are dependent on the GUP parameter αrelated to a minimum length. Then, by solving the geodesic deviation equations explicitly with appropriate boundary conditions, we show that α in the effective metric affects both the radial and angular components of the geodesic equation, particularly near the singularities.

关键词： effective metric generalized uncertainty principle geodesic deviation equation

Ghost imaging—its physics and application [Invited]

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Chinese Optics Letters 2024年第6期22卷 77-102页

作者： Yanhua Shih department of physics University of MarylandBaltimore CountyBaltimoreMD 21250USA

Since its first experimental demonstration, “ghost imaging” has attracted much attention, perhaps not only because of its interesting physics but also because of its attractive application. This review article discusses the physics and application of ghost imaging:(1) emphasizes the nonlocal two-photon interference nature of ghost imaging, including detailed analysis and calculations;(2) introduces three types of applications with unique advantages of ghost imaging, including a light detection and ranging device with imaging ability, namely, an Imaging Lidar or ILidar system;a turbulence-resistant, or turbulence-free, imaging technology;and a vibration-resistant X-ray microscope of high resolving *** article is prepared for a Special Issue of Chinese Optics Letters, intended for general audiences, especially young researchers and students who are interested in ghost imaging.

关键词： ghost imaging physics applications

Deep-learning-empowered synthetic dimension dynamics: morphing of light into topological modes

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Advanced Photonics 2024年第2期6卷 61-68页

作者： Shiqi Xia Sihong Lei Daohong Song Luigi Di Lauro Imtiaz Alamgir Liqin Tang Jingjun Xu Roberto Morandotti Hrvoje Buljan Zhigang Chen Nankai university TEDA Institute of Applied Physics School of Physics The MOE Key Laboratory of Weak-Light Nonlinear Photonics Shanxi university Collaborative Innovation Center of Extreme Optics INRS-EMT university of Zagreb Department of PhysicsFaculty of Science

Synthetic dimensions(SDs) opened the door for exploring previously inaccessible phenomena in high-dimensional space. However, construction of synthetic lattices with desired coupling properties is a challenging and unintuitive task. Here, we use deep learning artificial neural networks(ANNs) to construct lattices in real space with a predesigned spectrum of mode eigenvalues, and thus to validly design the dynamics in synthetic mode dimensions. By employing judiciously chosen perturbations(wiggling of waveguides at desired frequencies), we show resonant mode coupling and tailored dynamics in SDs. Two distinct examples are illustrated: one features uniform synthetic mode coupling, and the other showcases the edge defects that allow for tailored light transport and confinement. Furthermore, we demonstrate morphing of light into a topologically protected edge mode with modified Su–Schrieffer–Heeger photonic lattices. Such an ANN-assisted construction of SDs may advance toward “utopian networks,” opening new avenues for fundamental research beyond geometric limitations as well as for applications in mode lasing,optical switching, and communication technologies.

关键词： synthetic dimensions deep learning mode manipulation topological mode morphing photonic lattices

Tunable quantum anomalous Hall effects in ferromagnetic van der Waals heterostructures

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National Science Review 2024年第3期11卷 100-107页

作者： Feng Xue Yusheng Hou Zhe Wang Zhiming Xu Ke He Ruqian Wu Yong Xu Wenhui Duan Beijing Academy of Quantum Information Sciences State Key Laboratory of Low Dimensional Quantum physics Department of Physics Tsinghua University Guangdong Provincial Key Laboratory of Magnetoelectric physics and Devices Center for Neutron Science and Technology School of Physics Sun Yat-sen University State Key Laboratory of Surface physics Key Laboratory of Computational Physical Sciences and Department of PhysicsFudan University Frontier Science Center for Quantum Information department of physics and Astronomy University of California-Irvine Tencent Quantum Laboratory Tencent Technology(Shenzhen)Co.Ltd RIKEN Center for Emergent Matter Science(CEMS) Institute for Advanced Study Tsinghua University

The quantum anomalous Hall effect（QAHE） has unique advantages in topotronic applications, but it is still challenging to realize the QAHE with tunable magnetic and topological properties for building functional devices. Through systematic first-principles calculations, we predict that the in-plane magnetization induced QAHE with Chern numbers C = ±1 and the out-of-plane magnetization induced QAHE with high Chern numbers C = ±3 can be realized in a single material candidate, which is composed of van der Waals（vdW）coupled Bi and MnBi2Te4monolayers. The switching between different phases of QAHE can be controlled in multiple ways, such as applying strain or（weak） magnetic field or twisting the vdW materials. The prediction of an experimentally available material system hosting robust, highly tunable QAHE will stimulate great research interest in the field. Our work opens a new avenue for the realization of tunable QAHE and provides a practical material platform for the development of topological electronics.

关键词： quantum anomalous Hall effect topological quantum phase transition van der Waals heterostructures tunable Chern number high Chern number

Advances in laser-plasma interactions using intense vortex laser beams

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Science China(physics,Mechanics & Astronomy) 2024年第9期67卷 14-42页

作者： Yin Shi Xiaomei Zhang Alexey Arefiev Baifei Shen department of Plasma physics and Fusion Engineering University of Science and Technology of ChinaHefei 230026China department of physics Shanghai Normal UniversityShanghai 200234China department of Mechanical and Aerospace Engineering University of California at San DiegoLa JollaCA 92093USA

Low-intensity light beams carrying orbital angular momentum(OAM),commonly known as vortex beams,have garnered significant attention due to promising applications in areas ranging from optical trapping to *** recent years,there has been a surge in global research exploring the potential of high-intensity vortex laser beams and specifically their interactions with *** paper provides a comprehensive review of recent advances in this *** with conventional laser beams,intense vortex beams exhibit unique properties such as twisted phase fronts,OAM delivery,hollow intensity distribution,and spatially isolated longitudinal *** distinct characteristics give rise to a multitude of rich phenomena,profoundly influencing laser-plasma interactions and offering diverse *** paper also discusses future prospects and identifies promising general research areas involving vortex *** areas include low-divergence particle acceleration,instability suppression,high-energy photon delivery with OAM,and the generation of strong magnetic *** growing scientific interest and application potential,the study of intense vortex lasers is poised for rapid development in the coming years.

关键词： intense vortex laser orbital angular momentum laser plasma interactions high power laser high energy density science

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Effects of Ta content on microstructure and oxidation behavior of AlCoCrFeNiYTax high entropy alloy

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Rare Metals 2024年第9期43卷 4462-4475页

作者： Cang Gu Jun-Hao Hu Jian-Bo Song Cheng Xu Ming-Yu Hu Yu-Xuan Zhang Jiang Tian Chao Li Jing Feng Faculty of Materials Science and Engineering Kunming University of Science and Technology department of physics Hong Kong Baptist University

The oxidation behavior of the Al Co Cr Fe Ni YTaxhigh entropy alloy（HEA） doped with different Ta contents at 1100 °C is investigated. In this study, different reasons for the spallation of the oxide scales of HEAs without/with excessive Ta addition after 1000 h of oxidation are discussed, and the most suitable Ta doping content for this HEA is explored, in which the HEA exhibits both an exceptionally low oxidation rate, and the formation of oxide scales composed of intact a-Al2O3. Meanwhile, it is found that the addition of Ta can effectively inhibit the phase transition of β phase, which makes the surface of the oxide scale smoother. By combining our experimental results with Wagner–Hauffe theory, the influence of Ta drag effect on oxide scale growth is explained, which provides some theoretical guidance for the subsequent design of Al Co Cr Fe Ni HEAs, and can lead to the development of thermal barrier coatings at higher service temperature.

关键词： Al2O3 scales Elements diffusion High-entropy alloy Oxidation

Negative enthalpy alloys and local chemical ordering:a concept and route leading to synergy of strength and ductility

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National Science Review 2024年第4期11卷 172-184页

作者： Zibing An Tao Yang Caijuan Shi Shengcheng Mao Lihua Wang Ang Li Wei Li Xianmeng Xue Ming Sun Yifan Bai Yapeng He Fuzeng Ren Zhouguang Lu Ming Yan Yang Ren Chain-Tsuan Liu Ze Zhang Xiaodong Han Beijing Key Lab of Microstructure and Property of Advanced Materials College of Materials Science &Engineering Beijing University of Technology department of Materials Science and Engineering City University of Hong Kong Key Laboratory of Partial Acceleration physics& Technology Institute of High Energy PhysicsChinese Academy of Sciences department of Materials Science &Engineering Southern University of Science and Technology department of physics City University of Hong Kong State Key Laboratory of Silicon Materials Department of Materials Science and Engineering Zhejiang University

Solid solutions are ubiquitous in metals and alloys. Local chemical ordering(LCO) is a fundamental sub-nano/nanoscale process that occurs in many solid solutions and can be used as a microstructure to optimize strength and ductility. However, the formation of LCO has not been fully elucidated, let alone how to provide efficient routes for designing LCO to achieve synergistic effects on both superb strength and ductility. Herein, we propose the formation and control of LCO in negative enthalpy alloys. With engineering negative enthalpy in solid solutions, genetic LCO components are formed in negative enthalpy refractory high-entropy alloys(RHEAs). In contrast to conventional ‘trial-and-error' approaches, the control of LCO by using engineering negative enthalpy in RHEAs is instructive and results in superior strength(1160 MPa) and uniform ductility(24.5%) under tension at ambient temperature, which are among the best reported so far. LCO can promote dislocation cross-slip, enhancing the interaction between dislocations and their accumulation at large tensile strains; sustainable strain hardening can thereby be attained to ensure high ductility of the alloy. This work paves the way for new research fields on negative enthalpy solid solutions and alloys for the synergy of strength and ductility as well as new functions.

关键词： negative enthalpy alloys local chemical ordering strength ductility dislocation

Emergent topological ordered phase for the Ising-XY model revealed by cluster-updating Monte Carlo method

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Chinese physics B 2024年第4期33卷 386-400页

作者：马赫阳张万舟田彦婷丁成祥邓友金 College of physics Taiyuan University of TechnologyTaiyuan 030024China Hefei National Laboratory for Physical Sciences at the Microscale and department of Modern physics University of Science and Technology of ChinaHefei 230026China School of Microelectronics&Data Science Anhui University of TechnologyMaanshan 243002China Minjiang Collaborative Center for Theoretical physics College of Physics and Electronic Information EngineeringMinjiang UniversityFuzhou 350108China Shanghai Research Center for Quantum Sciences Shanghai 201315China

The two-component cold atom systems with anisotropic hopping amplitudes can be phenomenologically described by a two-dimensional Ising-XY coupled model with spatial *** low temperatures,theoretical predictions[***.A 72053604(2005)]and[arXiv:0706.1609]indicate the existence of a topological ordered phase characterized by Ising and XY disorder but with 2XY ***,due to ergodic difficulties faced by Monte Carlo methods at low temperatures,this topological phase has not been numerically *** propose a linear cluster updating Monte Carlo method,which flips spins without rejection in the anisotropy limit but does not change the *** this scheme and conventional Monte Carlo methods,we succeed in revealing the nature of topological phases with half-vortices and domain *** the constructed global phase diagram,Ising and XY-type transitions are very close to each other and differ significantly from the schematic phase diagram reported *** also propose and explore a wide range of quantities,including magnetism,superfluidity,specific heat,susceptibility,and even percolation susceptibility,and obtain consistent and reliable ***,we observed first-order transitions characterized by common intersection points in magnetizations for different system sizes,as opposed to the conventional phase transition where Binder cumulants of various sizes share common *** critical exponents of different types of phase transitions are reasonably *** results are useful to help cold atom experiments explore the half-vortex topological phase.

关键词： topological phase transition Ising-XY model Monte Carlo method half vortex