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Variational quantum algorithms for scanning the complex spectrum of non-Hermitian systems

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Frontiers of physics 2024年第4期19卷 275-285页

作者： Xu-Dan Xie Zheng-Yuan xue Dan-Bo Zhang Key Laboratory of Atomic and Subatomic Structure and Quantum Control(Ministry of Education) Guangdong Basic Research Center of Excellence for Structure and Fundamental Interactions of Matterand School of PhysicsSouth China Normal UniversityGuangzhou 510006China Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials Guangdong–Hong Kong Joint Laboratory of Quantum Matterand Frontier Research Institute for PhysicsSouth China Normal UniversityGuangzhou 510006China

Solving non-Hermitian quantum many-body systems on a quantum computer by minimizing the variational energy is challenging as the energy can be ***,we propose a variational quantum algorithm for solving the non-Hermitian Hamiltonian by minimizing a type of energy variance,where zero variance can naturally determine the eigenvalues and the associated left and right ***,the energy is set as a parameter in the cost function and can be tuned to scan the whole spectrum efficiently by using a two-step optimization *** numerical simulations,we demonstrate the algorithm for preparing the left and right eigenstates,verifying the biorthogonal relations,as well as evaluating the *** also investigate the impact of quantum noise on our algorithm and show that its performance can be largely improved using error mitigation ***,our work suggests an avenue for solving non-Hermitian quantum many-body systems with variational quantum algorithms on near-term noisy quantum computers.

关键词： quantum algorithm non-Hermitian physics quantum manybody systems

Relationship between the Stratospheric Arctic Vortex and Surface Air Temperature in the Midlatitudes of the Northern Hemisphere

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Journal of Meteorological Research 2024年第1期38卷 39-52页

作者： xue RAN Dingzhu HU Yang ZHANG Mei-Chen LIU Key Laboratory of Meteorological Disaster Ministry of Education(KLME)/Joint International Research Laboratory of Climate and Environmental Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science&TechnologyNanjing 210044 School of Atmospheric Sciences Nanjing UniversityNanjing 210023

It is known that different relationships exist between the strength and displacement of the stratospheric polar vortex(SPV),and the surface air temperature(SAT)patterns in Eurasia and North America,but the mechanisms behind these relationships remain unclear,especially on an interannual *** on empirical orthogonal function(EOF)analysis using NCEP reanalysis data over 1958–2018,this study attempts to ascertain the relationship between the SPV intensity and displacement over the Arctic and the SATs in the midlatitudes of the Northern *** results indicate that a strengthened SPV corresponds to an SAT increase in Eurasia and a decrease in eastern North America and *** the SPV is shifted towards Eurasia,however,a corresponding SAT increase occurs in both North America and Eurasia,with a larger increase in North America than in ***,a strengthened SPV tends to correspond to a positive North Atlantic Oscillation-like circulation in the troposphere with negative geopotential height(GH)anomalies in Greenland and eastern North American continent and positive GH anomalies to the north of 45°N in Eurasia,which corresponds to lower SATs in North America than in ***,when the SPV shifted towards Eurasia,it was accompanied by a positive Pacific/North American-like pattern with a deepened Aleutian low,which corresponds to the increasing SATs in North *** tropospheric circulation changes are related to the response of tropospheric planetary wave activity to the SPV.A strengthened SPV corresponds to the weakening of tropospheric planetary wave-1 waves,which is accompanied by a negative GH in North America but a positive GH in *** the SPV shifted towards Eurasia,the tropospheric planetary wave-1(-2)waves strengthened(weakened),and the combined effects of the planetary wave-1 and wave-2 waves would cause positive GH anomalies in both Eurasia and North America.

关键词： stratospheric polar vortex surface air temperature teleconnection patterns planetary waves

Ant-nest-inspired porous structure for MXene composites with high-performance energy-storage and actuating multifunctions

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Nano Research 2024年第7期17卷 6673-6685页

作者： Yi Wang Guanfeng xue Zhiling Luo Wei Zhang Luzhuo Chen Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials College of Physics and EnergyFujian Normal UniversityFuzhou 350117China Fujian Provincial Collaborative Innovation Center for Advanced High-Field Superconducting Materials and Engineering Fuzhou 350117China

Integrating energy-storage devices(supercapacitors)and shape-deformation devices(actuators)advances the miniaturization and multifunctional development of soft ***,soft robots necessitate supercapacitors with high energy-storage performance and actuators with excellent actuation ***,inspired by ant nests,we present a porous structure fabricated by MXene-graphene-methylcellulose(M-GMC)composite,which overcomes the self-stacking of MXene nanosheets and offers a larger specific surface *** porous structure provides more channels and active sites for electrolyte ions,resulting in high energy storage *** areal capacitance of the M-GMC electrode reaches up to 787.9 mF·cm^(−2),significantly superior to that of the pristine MXene electrode(449.1 mF·cm^(−2)).Moreover,the M-GMC/polyethylene bilayer composites with energy storage and multi-responsive actuation functions are *** M-GMC is used as the electrode and the polyethylene is used as the encapsulation layer of the quasi-solid-state ***,the actuators fabricated by the bilayer composites can be driven by light or low voltage(≤9 V).The maximum bending curvature is up to 5.11 cm^(−1).Finally,a smart gripper and a fully encapsulated smart integrated circuit based on the M-GMC/polyethylene are *** smart gripper enables programmable control with multi-stage *** applications realize the intelligence and miniaturization of soft *** ant-nest-inspired M-GMC composites would provide a promising development strategy for soft robots and smart integrated devices.

关键词： MXene graphene ant nest supercapacitor actuator multi-functional

Toward a fundamental understanding of the heterogeneous multiphysics behaviors of silicon monoxide/graphite composite anodes

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Carbon Energy 2024年第1期6卷 142-158页

作者： Xiang Gao Suli Li Jiachen xue Dianyang Hu Jun Xu Department of Mechanical Engineering and Engineering Science University of North Carolina at CharlotteCharlotteNorth CarolinaUSA Vehicle Energy and Safety Laboratory(VESL) Battery ComplexityAutonomous Vehicleand Electrification(BATT CAVE)Research CenterUniversity of North Carolina at CharlotteCharlotteNorth CarolinaUSA Zhuhai CosMX Battery Co.Ltd. ZhuhaiGuangdongChina School of Data Science University of North Carolina at CharlotteCharlotteNorth CarolinaUSA

Silicon monoxide(SiO)(silicon[Si]mixed with silicon dioxide[SiO_(2)])/graphite(Gr)composite material is one of the most commercially promising anode materials for the next generation of high-energy-density lithium-ion *** major bottleneck for SiO/Gr composite anode is the poor cyclability arising from the stress/strain behaviors due to the mismatch between two heterogenous materials during the lithiation/delithiation *** date,a meticulous and quantitative understanding of the highly nonlinear coupling behaviors of such materials is still ***,an electro–chemo–mechanics-coupled detailed model containing particle geometries is *** underlying mechanism of the regulation between SiO and Gr components during electrochemical cycling is quantitatively *** discover that increasing the SiO weight percentage(wt%)reduces the utilization efficiency of the active materials at the same 1C rate charging and enhances the hindering effects of stress-driven flux on *** addition,the mechanical constraint demonstrates a balanced effect on the overall performance of cells and the local behaviors of *** study provides new insights into the fundamental interactions between SiO and Gr materials and advances the investigation methodology for the design and evaluation of next-generation high-energydensity batteries.

关键词： interactions lithium-ion batteries mechanical constraint multiphysics modeling Si-based anode

Exploring multiple phases and first-order phase transitions in Kármán Vortex Street

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Science China(Physics,Mechanics & Astronomy) 2024年第11期Mechanics & Astronomy) .卷 51-58页

作者： Xu Li Xing Xiang Tingting xue Limin Wang Xiaosong Chen School of Systems Science and Institute of Nonequilibrium Systems Beijing Normal University State Key Laboratory of Multiphase Complex Systems Institute of Process Engineering Chinese Academy of Sciences School of Chemical Engineering University of Chinese Academy of Sciences

Kármán Vortex Street, a fascinating phenomenon of fluid dynamics, has intrigued the scientific community for a long time. Many researchers have dedicated their efforts to unraveling the essence of this intriguing flow pattern. Here, we apply the lattice Boltzmann method with curved boundary conditions to simulate flows around a circular cylinder and study the emergence of Kármán Vortex Street using the eigen microstate approach, which can identify phase transition and its order-parameter. At low Reynolds number, there is only one dominant eigen microstate W1of laminar flow. At Rec1= 53.6, there is a phase transition with the emergence of an eigen microstate pair W2,3of pressure and velocity fields. Further at Rec2= 56, there is another phase transition with the emergence of two eigen microstate pairs W4,5and W6,7. Using the renormalization group theory of eigen microstate,both phase transitions are determined to be first-order. The two-dimensional energy spectrum of eigen microstate for W1, W2,3after Rec1, W4-7after Rec2exhibit-5/3 power-law behavior of Kolnogorov's K41 theory. These results reveal the complexity and provide an analysis of the Kármán Vortex Street from the perspective of phase transitions.

关键词： Kármán Vortex Street first-order phase transition eigen microstate approach renormalization group theory of eigen microstate

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Output Feedback Stabilization of High-Order Nonlinear Time-Delay Systems With Low-Order and High-Order Nonlinearities

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1304-1306页

作者： Meng-Meng Jiang Kemei Zhang xue-Jun Xie School of Mathematics Science Liaocheng UniversityLiaocheng 252059China School of Mathematics Science Qufu Normal UniversityQufu 273165China Institute of Automation Qufu Normal UniversityQufu 273165China

Dear Editor,to This letter deals with the output feedback stabilization of a class of high-order nonlinear time-delay systems with more general low-order and high-order *** constructing reduced-order observer,based on homogeneous domination theory together with the adding a power integrator method,an output feedback controller is developed guarantee the equilibrium of the closed system globally uniformly asymptotically stable.

关键词： Nonlinear stabilization guarantee

Recent Advances in Asymmetric Structural Composites for Excellent Electromagnetic Interference Shielding: A Review

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Chinese Journal of Polymer Science 2024年第6期42卷 693-710页

作者： Ying Zhou Bai xue Lan Xie Chang-Mei Wu Qiang Zheng Department of Polymer Materials and Engineering College of Materials and Metallurgy Guizhou University National Engineering Research Center for Compounding and Modification of Polymer Materials National and Local Joint Engineering Research Center for Functional Polymer Membrane Materials and Membrane Processes State Key Laboratory of Public Big Data Guizhou University Department of Polymer Science and Engineering Zhejiang University

Since electromagnetic pollution is detrimental to human health and the environment, numerous efforts have been successively made to achieve excellent electromagnetic interference shielding effectiveness(EMI SE) via designing the hierarchical structures for electromagnetic interference(EMI) shielding polymer composites. Among the plentiful structures, the asymmetric structures are currently a hot spot, principally categorizing into multi-layered, porous, fibrous, and segregated asymmetric structures, which endows the high EMI shielding performance for polymer composites incorporated with magnetic, conductive, and/or dielectric micro/nano-fillers, due to the “absorption-reflection-reabsorption” shielding mechanism. Therefore, this review provides the retrospection and summary of the efforts with respect to abundant asymmetric structures and multifunctional micro/nano-fillers for enhancing EMI shielding properties, which is conducive to the booming development of polymeric EMI shielding materials for the promising prospect in modern electronics and 5-generation(5G) technology.

关键词： Asymmetric structure Microano functional filler Polymer composite Electromagnetic interference shielding

Comparison of Rotating Stall Warning by Different Methods for Variable Speed Configurations in a Contra-Rotating Compressor

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Journal of Thermal Science 2024年第4期33卷 1379-1393页

作者： xue Fei WANG Yan'gang LIU Qian WU Tong LIU Hanru School of Power and Energy Northwestern Polytechnical UniversityXi’an710072China

Stall in compressors can cause performance degradation and even lead to *** unacceptable consequences can be avoided by timely monitoring stall inception and taking effective *** paper focused on the rotating stall warning in a low-speed axial contra-rotating ***,the stall disturbance characteristics under different speed configurations were *** results showed that as the speed ratio(RR)increased,the stall disturbance propagation speed based on the rear rotor speed gradually ***,the standard deviation(SD)method,the cross-correlation(CC)method,and the discrete wavelet transform(DWT)method were employed to obtain the stall initiation moments of three different speed *** was found that the SD and CC methods did not achieve significant stall warning results in all three speed ***,the stall initiation moment obtained by the DWT method at RR=1.125 was one period after the stall had fully developed,which was ***,a stall warning method was developed in the present work based on the long short-term memory(LSTM)regression *** applying the LSTM model,the predicted stall initiation moments of three speed configurations were at the 557th,518th,and 333rd revolution,which were44,2,and 74 revolutions ahead of stall onset moments,***,in scenarios where a minor disturbance preceded the stall,the stall warning effect of the LSTM was greatly improved in comparison with the aforementioned three *** contrast,when the pressure fluctuation before the stall was relatively small,the differences between the stall initiation moments predicted by these four methods were not significant.

关键词： contra-rotating compressor stall disturbance stall initiation moment long short-term memory(LSTM) stall warning

Fully sprayed MXene-based high-performance flexible piezoresistive sensor for image recognition

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Nano Materials Science 2024年第1期6卷 77-85页

作者： Zhi-Dong Zhang xue-Feng Zhao Qing-Chao Zhang Jie Liang Hui-Nan Zhang Tian-Sheng Zhang Chen-Yang xue Key Laboratory of Instrumentation Science&Dynamic Measurement of Ministry of Education North University of ChinaTaiyuan030051People's Republic of China State Key Laboratory of ASIC and System Shanghai Institute of Intelligent Electronics&SystemsSchool of MicroelectronicsFudan UniversityShanghai200433People's Republic of China Shanxi Hosipital of Acupuncture and Moxibustion Taiyuan030006People's Republic of China

High-performance flexible pressure sensors provide comprehensive tactile perception and are applied in human activity monitoring,soft robotics,medical treatment,and human-computer ***,these flexible pressure sensors require extensive nano-architectural design and complicated manufacturing and are ***,a highly sensitive,flexible piezoresistive tactile sensor is designed and fabricated,consisting of three main parts:the randomly distributed microstructure on T-ZnOw/PDMS film as a top substrate,multilayer Ti_(3)C_(2)-MXene film as an intermediate conductive filler,and the few-layer Ti_(3)C_(2)-MXene nanosheetbased interdigital electrodes as the bottom *** MXene-based piezoresistive sensor with randomly distributed microstructure exhibits a high sensitivity over a broad pressure range(less than 10 kPa for 175 kPa^(-1))and possesses an out-standing permanence of up to 5000 ***,a 16-pixel sensor array is designed,and its potential applications in visualizing pressure distribution and an example of tactile feedback are *** fully sprayed MXene-based pressure sensor,with high sensitivity and excellent durability,can be widely used in,electronic skin,intelligent robots,and many other emerging technologies.

关键词： Piezoresistive sensor Ti_(3)C_(2)-MXene T-ZnOw/PDMS film Randomly distributed microstructure