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The higher-order topological pumping explored in the 2D acoustic crystal

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Science China(physics,Mechanics & Astronomy) 2024年第2期67卷 127-133页

作者： Yanqiu Wang Bin Liang Jianchun Cheng Key Laboratory of modern Acoustics Ministry of EducationInstitute of AcousticsDepartment of PhysicsNanjing UniversityNanjing 210093China Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing 210093China

The topological pumping has been instrumental in advancing our understanding of topological phase transitions in various physical systems,which can be extended to uncover intriguing higher-order topological phases in the lower-dimensional ***,we propose a theoretical exploration of topological dipole pumping on an acoustic square superlattice by cyclically modulating intracell couplings,which shares the topological nature of an extended three-dimensional system with chiral hinge *** the multipole chiral numbers,we characterize the higher-order topological phases that arise during the *** evolution of topological phase transitions is verified by numerical simulations and shows corner states are transferred across the *** findings can inspire the construction of chiral hinge states in artificial crystals,opening up new possibilities for the design of devices allowing the unidirectional propagation of sound.

关键词： topological phases of matter Thouless pumping acoustic metamaterial

High-order time-reversal symmetry breaking normal state

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Science China(physics,Mechanics & Astronomy) 2024年第3期67卷 136-148页

作者： Meng Zeng Lun-Hui Hu Hong-Ye Hu Yi-Zhuang You Congjun Wu Department of physics University of CaliforniaSan DiegoCalifornia 92093USA Department of physics Zhejiang UniversityHangzhou 310058China New Cornerstone Science Laboratory Department of PhysicsSchoolof ScienceWestlake UniversityHangzhou 30024China institute for Theoretical Sciences Westlake UniversityHangzhou 310024China Key Laboratory for Quantum Materials of zhejiang Province School of ScienceWestlake UniversityHangzhou 310024China institute of Natural Sciences Westlake Institute for Advanced StudyHangzhou 310024China

Spontaneous time-reversal symmetry breaking plays an important role in studying strongly correlated unconventional *** two superconducting gap functions with different symmetries compete,the relative phase channel(θ_(-)≡θ_(1)-θ_(2))exhibits an Ising-type Z_(2) symmetry due to the second order Josephson coupling,where θ_(1,2) are the phases of two gap *** contrast,the U(1) symmetry in the channel of θ_(+)≡(θ_(1)+θ_(2))/2 is *** phase locking,i.e.,ordering of θ_(-),can take place in the phase fluctuation regime before the onset of superconductivity,i.e.,when θ_(+) is *** θ_(-) is pinned at ±π/2,then timereversal symmetry is broken in the normal state,otherwise,if θ_(-)=0,or,π,rotational symmetry is broken,leading to a nematic normal *** both cases,the order parameters possess a 4-fermion structure beyond the scope of mean-field theory,which can be viewed as a high order symmetry *** employ an effective two-component XY-model assisted by a renormalization group analysis to address this *** a natural by-product,we also find the other interesting intermediate phase corresponds to ordering of θ_+ but with θ_(-)*** is the quartetting,or,charge-4e,superconductivity,which occurs above the low temperature Z_(2)-breaking charge-2e superconducting *** results provide useful guidance for studying novel symmetry breaking phases in strongly correlated superconductors.

关键词： superconductivity strong correlation time-reversal breaking charge-4e

On the improved dynamics approach in loop quantum black holes

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Communications in Theoretical physics 2024年第3期76卷 138-143页

作者： Hongchao Zhang Wen-Cong Gan Yungui Gong Anzhong Wang institute for Theoretical physics&Cosmology Zhejiang University of TechnologyHangzhou310023China United Center for Gravitational Wave physics(UCGWP) Zhejiang University of TechnologyHangzhou310023China College of physics and Communication Electronics Jiangxi Normal UniversityNanchang 330022China GCAP-CASPER Physics DepartmentBaylor UniversityWacoTX 76798-7316United States of America School of physics Huazhong University of Science and TechnologyWuhanHubei 430074China Department of physics School of Physical Science and TechnologyNingbo UniversityNingboZhejiang 315211China

In this paper,we consider the B?hmer–Vandersloot(BV)model of loop quantum black holes obtained from the improved dynamics *** adopt the Saini–Singh gauge,in which it was found analytically that the BV spacetime is geodesically *** show that black/white hole horizons do not exist in this geodesically complete ***,there exists only an infinite number of transition surfaces,which always separate trapped regions from anti-trapped *** on the improved dynamics approach adopted in other models of loop quantum black holes are also given.

关键词： loop quantum gravity black hole dynamics approach

Quantum algorithms for matrix operations and linear systems of equations

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Communications in Theoretical physics 2024年第3期76卷 100-112页

作者： Wentao Qi Alexandr I Zenchuk Asutosh Kumar Junde Wu School of Mathematical Sciences Zhejiang UniversityHangzhou 310027China Federal Research Center of Problems of Chemical physics and Medicinal Chemistry RAS ChernogolovkaRussia P.G.Department of physics Gaya CollegeMagadh UniversityRampurGaya 823001India Harish-Chandra Research institute HBNIChhatnag RoadJhunsiPrayagraj 211019India Vaidic and modern physics Research Centre Bhagal BhimBhinmalJalore 343029India

Fundamental matrix operations and solving linear systems of equations are ubiquitous in scientific *** the‘sender-receiver’model,we propose quantum algorithms for matrix operations such as matrix-vector product,matrix-matrix product,the sum of two matrices,and the calculation of determinant and inverse *** encode the matrix entries into the probability amplitudes of the pure initial states of *** applying proper unitary transformation to the complete quantum system,the desired result can be found in certain blocks of the receiver’s density *** quantum protocols can be used as subroutines in other quantum ***,we present an alternative quantum algorithm for solving linear systems of equations.

关键词： matrix operation systems of linear equations ‘sender-receiver’quantum computation model quantum algorithm

■ Cross Sections and the Λc+ Electromagnetic Form Factors within the Extended Vector Meson Dominance Model

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Chinese physics Letters 2024年第2期 41-46页

作者：陈诚闫冰谢聚军 institute of modern physics Chinese Academy of Sciences School of Nuclear Sciences and Technology University of Chinese Academy of Sciences College of Mathematics and physics Chengdu University of Technology Southern Center for Nuclear-Science Theory (SCNT) Institute of Modern PhysicsChinese Academy of Sciences

Within the extended vector meson dominance model, we investigate the ■reaction and the electromagnetic form factors of the charmed baryon Λc+. The model parameters are determined by fitting them to the cross sections of the process ■ and the magnetic form factor |GM| of Λc+. By considering four charmonium-like states, called ψ(4500), ψ(4660), ψ(4790), and ψ(4900), we can well describe the current data on the ■reaction from the reaction threshold up to 4.96 GeV. In addition to the total cross sections and |GM|, the ratio |GE/GM| and the effective form factor |Geff| for Λc+are also calculated, and found that these calculations are consistent with the experimental data. Within the fitted model parameters, we have also estimated the charge radius of the charmed Λc+baryon.

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Reshaping the Cortical Connectivity Gradient by Long-Term Cognitive Training During Development

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Neuroscience Bulletin 2024年第1期40卷 50-64页

作者： Tianyong Xu Yunying Wu Yi Zhang Xi-Nian Zuo Feiyan Chen Changsong Zhou Bio-X Laboratory School of PhysicsZhejiang UniversityHangzhou 310027China Qiushi Academy for Advanced Studies Zhejiang UniversityHangzhou 310027China State Key Laboratory of modern Optical Instrumentation College of Optical Science and EngineeringZhejiang UniversityHangzhou 310027China State Key Laboratory of Cognitive Neuroscience and Learning Bejing Normal UniversityBeijing 100875China Developmental Population Neuroscience Research Center IDG/McGovern Institute for Brain ResearchBeijing Normal UniversityBeijing 100875China zhejiang Province Key Laboratory of Quantum Technology and Devices Zhejiang UniversityHangzhou 310027China Department of physics Centre for Nonlinear Studies and Beijing-Hong Kong-Singapore Joint Centre for Nonlinear and Complex Systems(Hong Kong)Institute of Computational and Theoretical StudiesHong Kong Baptist UniversityHong Kong 999077China

The organization of the brain follows a topologi-cal hierarchy that changes dynamically during ***,it remains unknown whether and how cognitive training administered over multiple years during develop-ment can modify this hierarchical *** measuring the brain and behavior of school children who had carried out abacus-based mental calculation(AMC)training for five years(starting from 7 years to 12 years old)in pre-training and post-training,we revealed the reshaping effect of long-term AMC intervention during development on the brain hierarchical *** observed the development-induced emergence of the default network,AMC training-promoted shifting,and regional changes in cortical ***,the training-induced gradient changes were located in visual and somatomotor areas in association with the visuospatial/motor-imagery *** found that gradient-based features can predict the math ability within *** findings provide novel insights into the dynamic nature of network recruitment impacted by long-term cognitive training during development.

关键词： Connectivity gradient Cognitive training Development Neural plasticity Abacus-based mental calculation

Uniformity Control of Scanned Beam in 300 MeV Proton and Heavy Ion Accelerator Complex at SESRI

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原子能科学技术 2024年第4期58卷 705-713页

作者： HOU Lingxiao YUAN Youjin SHEN Guodong RUAN Shuang LIU Jie ZHU Yunpeng WANG Geng GUO Hongliang LYU Mingbang GAO Daqing XU Zhiguo SHENG Lina YANG Jiancheng institute of modern physics Chinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China

In recent years,heavy ion accelerator technology has been rapidly developing worldwide and widely applied in the fields of space radiation simulation and particle ***,a very high uniformity in the irradiation area is required for the extracted ion beams,which is crucial because it directly affects the experimental precision and therapeutic ***,ultra-large-area and high-uniformity scanning are crucial requirements for spacecraft radiation effects assessment and serve as core specification for beamline terminal *** the 300 MeV proton and heavy ion accelerator complex at the Space Environment Simulation and Research Infrastructure(SESRI),proton and heavy ion beams will be accelerated and ultimately delivered to three irradiation *** order to achieve the required large irradiation area of 320 mm×320 mm,horizontal and vertical scanning magnets are used in the extraction beam ***,considering the various requirements for beam species and energies,the tracking accuracy of power supplies(PSs),the eddy current effect of scanning magnets,and the fluctuation of ion bunch structure will reduce the irradiation *** mitigate these effects,a beam uniformity optimization method based on the measured beam distribution was proposed and applied in the accelerator complex at *** the experiment,the uniformity is successfully optimized from 75%to over 90%after five iterations of adjustment to the PS *** this paper,the method and experimental results were introduced.

关键词： heavy ion accelerator beam uniformity scanning magnet MIC

Estimating the yield stress of soft materials via laser-induced breakdown spectroscopy

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Chinese physics B 2024年第3期33卷 428-432页

作者：龚书航李亚举钱东斌叶晋瑞赵扣曾强陈良文张少锋杨磊马新文 Advanced Energy Science and Technology Guangdong LaboratoryHuizhou 516000China institute of modern physics Chinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China

Taking three typical soft samples prepared respectively by loose packings of 77-,95-,and 109-μm copper grains as examples,we perform an experiment to investigate the energy-dependent laser-induced breakdown spectroscopy(LIBS)of soft *** discovered a reversal phenomenon in the trend of energy dependence of plasma emission intensity:increasing initially and then decreasing separated by a well-defined critical *** trend reversal is attributed to the laser-induced recoil pressure at the critical energy just matching the sample's yield *** a result,a one-to-one correspondence can be well established between the samples'yield stress and the critical energy that is easily obtainable from LIBS *** allows us to propose an innovative method for estimating the yield stress of soft materials via LIBS with attractive advantages including in-situ remote detection,real-time data collection,and minimal destructive to sample.

关键词： laser-induced breakdown spectroscopy soft materials yield stress

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费曼积分作为一类新的特殊函数

Science Bulletin 2024年第7期69卷 859-862页

作者：刘志峰马滟青王辰宇 zhejiang institute of modern physics School of PhysicsZhejiang UniversityHangzhou 310027China School of physics Peking UniversityBeijing 100871China Center for High Energy physics Peking UniversityBeijing 100871China Max-Planck-Institut für Physik Garching 85748Germany

Feynman integrals(FIs)serve as fundamental components of perturbative quantum field *** study of FIs is important for both exploring the mysteries of quantum field theories and their phenomenological applications,particularly in particle physics.A significant amount of effort has been devoted to analytically calculating FIs,with the goal of expressing them as linear combinations of special functions.

关键词： functions. theory. 特殊函数