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Piezo-/ferroelectric phenomena in biomaterials: A brief review of recent progress and perspectives

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Science China(Physics,Mechanics & Astronomy) 2020年第7期63卷 29-46页

作者： Yao Sun KaiYang Zeng Tao Li Department of Mechanical Engineering National University of SingaporeSingapore 546080Singapore center for spintronics and quantum systems State Key Laboratory for Mechanical Behavior of MaterialsSchool of Materials Science and EngineeringXi'an Jiaotong UniversityXi'an 710049China

There have been overwhelming observations of piezo-/ferroelectric phenomena in many biological tissues and macromolecules,boosting the development of bio-based smart devices and the applications using electromechanical coupling phenomena in biological *** electromechanical coupling is believed to be responsible for various biophysical behaviors and remarkable biomaterial *** the abundant phenomenal observations,the fundamental understanding of the piezo-/ferroelectric effect in biomaterials/systems and the rational design of biobased macroscopic materials with desired piezoelectric responses are still *** this review,we firstly present remarkable historical events on the development of piezo-/ferroelectricity in biomaterials,followed by a brief overview of the fundamental physics of piezo-/*** developments of biopiezo-/bioferroelectricity in protein-based biomaterials and their implications are highlighted *** experimental studies,to identify the intrinsic piezo-/ferroelectric properties from other effects or artifacts is usually *** issue is also addressed and discussed in detail,especially using piezoelectric force microscopy(PFM)and spectroscopy techniques to investigate the local piezo-/ferroelectric phenomena in nanostructured materials are highlighted emphatically.

关键词： biomaterials electromechanical coupling piezoelectric ferroelectric piezoresponse force microscopy

Decision making module based on stochastic magnetic tunnel junctions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 202-209页

作者： Yifan Miao Li Zhao Yajun Zhang Zhe Yuan center for Advanced quantum Studies and Department of Physics Beijing Normal University Institute for Nanoelectric Devices and quantum Computing Fudan University Interdisciplinary center for Theoretical Physics and Information Sciences Fudan University

In biological neural systems, noise is ubiquitous but does not affect the correct decisions made in the complex cognitive ***-making in biological neural system is typically achieved by accumulating input information over a period of *** by recent developments in neurosciences, we design a decision-making module based on spintronic devices, utilizing superparamagnetic tunnel junctions as artificial neurons. The feasibility of this decision-making module is verified through circuit simulations. Taking a multi-layer perceptron as an example, the module significantly improves the accuracy of the perceptron in the handwritten digit recognition task. Furthermore, the spintronic decision-making module offers advantages over the conventional pooling methods, such as adaptive decision time, high performance and the absence of analog-to-digital conversion. The decision-making module is flexible to be integrated into artificial neural networks and provides a general yet effective solution to enhance performance against device noise.

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Dissipative quantum phase transition in a biased Tavis-Cummings model

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Chinese Physics B 2020年第4期29卷 296-302页

作者： Zhen Chen Yueyin Qiu Guo-Qiang Zhang Jian-Qiang You quantum Physics and quantum Information Division Beijing Computational Science Research CenterBeijing 100193China Interdisciplinary center of quantum Information and Zhejiang Province Key Laboratory of quantum Technology and Device Department of Physics and State Key Laboratory of Modern Optical InstrumentationZhejiang UniversityHangzhou 310027China Laboratory of quantum Information Institute for Quantum Information and SpintronicsSchool of ScienceChongqing University of Posts and TelecommunicationsChongqing 400065China

We study the dissipative quantum phase transition(QPT)in a biased Tavis–Cummings model consisting of an ensemble of two-level systems(TLSs)interacting with a cavity mode,where the TLSs are pumped by a drive *** our proposal,we use a dissipative TLS ensemble and an active cavity with effective *** the weak drive-field limit,the QPT can occur under the combined actions of the loss and gain of the *** to the active cavity,the QPT behavior can be much differentiated even for a finite strength of the drive field on the TLS ***,we propose to implement our scheme based on the dissipative nitrogen-vacancy(NV)centers coupled to an active optical cavity made from the gainmedium-doped ***,we show that the QPT can be measured by probing the transmission spectrum of the cavity embedding the ensemble of the NV centers.

关键词： quantum phase transition dissipative ensemble of two-level systems active optical cavity Tavis-Cummings model

Electronic transport properties of Co cluster-decorated graphene

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Chinese Physics B 2018年第6期27卷 81-86页

作者： Chao-Yi Cai Jian-Hao Chen International center for quantum Materials Peking UniversityCollaborative Innovation Center of Quantum Matte

Interactions of magnetic elements with graphene may lead to various electronic states that have potential *** report an in-situ experiment in which the quantum transport properties of graphene are measured with increasing cobalt coverage in continuous ultra-high vacuum environment. The results show that e-beam deposited cobalt forms clusters on the surface of graphene, even at low sample temperatures. Scattering of charge carriers by the absorbed cobalt clusters results in the disappearance of the Shubnikov–de Haas（Sd H） oscillations and the appearance of negative magnetoresistance（MR）which shows no sign of saturation up to an applied magnetic field of 9 T. We propose that these observations could originate from quantum interference driven by cobalt disorder and can be explained by the weak localization theory.

关键词： in situ quantum transport negative magnetoresistance weak localization

Superfluidity of Bose Einstein condensates in ultracold atomic gases

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Chinese Physics B 2015年第5期24卷 56-70页

作者：朱起忠吴飙 International center for quantum Materials School of Physics Peking University Collaborative Innovation center of quantum Matter Peking University Wilczek quantum center Zhejiang University of Technology

Liquid helium 4 had been the only bosonic superfluid available in experiments for a long time. This situation was changed in 1995, when a new superfluid was born with the realization of the Bose-Einstein condensation in ultracold atomic gases. The liquid helium 4 is strongly interacting and has no spin; there is almost no way to change its parameters, such as interaction strength and density. The new superfluid, Bose-Einstein condensate （BEC）, offers various advantages over liquid helium. On the one hand, BEC is weakly interacting and has spin degrees of freedom. On the other hand, it is convenient to tune almost all the parameters of a BEC, for example, the kinetic energy by spin--orbit coupling, the density by the external potential, and the interaction by Feshbach resonance. Great efforts have been devoted to studying these new aspects, and the results have greatly enriched our understanding of superfluidity. Here we review these developments by focusing on the stability and critical velocity of various superfluids. The BEC systems considered include a uniform superfluid in free space, a superfluid with its density periodically modulated, a superfluid with artificially engineered spinorbit coupling, and a superfluid of pure spin current. Due to the weak interaction, these BEC systems can be well described by the mean-field Gross-Pitaevskii theory and their superfluidity, in particular critical velocities, can be examined with the aid of Bogoliubov excitations. Experimental proposals to observe these new aspects of superfluidity are discussed.

关键词： superfluidity Bose-Einstein condensation ultracold atomic gases Gross-Pitaevskii theory

Mode Structures and Damping of Quantized Spin Waves in Ferromagnetic Nanowires

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Chinese Physics Letters 2020年第8期37卷 142-146页

作者： Qingwei Fu Yong Li Lina Chen Fusheng Ma Haotian Li Yongbing Xu Bo Liu Ronghua Liu and Youwei Du National Laboratory of Solid State Microstructures School of Physics and Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China Jiangsu Key Laboratory of Opto-Electronic Technology Center for Quantum Transport and Thermal Energy ScienceSchool of Physics and TechnologyNanjing Normal UniversityNanjing 210023China York-Nanjing Joint center(YNJC)for spintronics and Nanoengineering School of Electronics Science and EngineeringNanjing UniversityNanjing 210093China spintronics and Nanodevice Laboratory Department of ElectronicsUniversity of YorkYork YO105DDUnited Kingdom Key Laboratory of spintronics Materials Devices and Systems of Zhejiang ProvinceHangzhou 311300China

Magnonic devices based on spin waves are considered as a new generation of energy-efficient and high-speed devices for storage and processing of *** we experimentally demonstrate that three distinct dominated magneto-dynamic modes are excited simultaneously and coexist in a transversely magnetized ferromagnetic wire by the ferromagnetic resonance(FMR)*** the uniform FMR mode,the spin-wave well mode,the backward volume magnetostatic spin-wave mode,and the perpendicular standing spin-wave mode are experimentally observed and further confirmed with more detailed spatial profiles by micromagnetic ***,our experimental approach can also access and reveal damping coefficients of these spin-wave modes,which provides essential information for development of magnonic devices in the future.

关键词： technique. ferromagnetic wave

Direct evidence of high temperature superconductivity in one-unit-cell FeSe films on SrTiO_3 substrate by transport and magnetization measurements

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Chinese Physics B 2015年第11期24卷 15-22页

作者：邢颖王健 International center for quantum Materials School of Physics Peking University Collaborative Innovation center of quantum Matter

Zero resistance and Meissner effect are two crucial experimental evidences of superconductivity in determining a new kind of superconductor, which can be detected by transport and diamagnetic measurements. In this paper, we briefly review the main transport and magnetization results on the one unit cell （1-UC） FeSe films grown on SrTiO3 （STO） substrates from our team in recent years, which identify the high temperature superconductivity in 1-UC FeSe films.

关键词： two-dimensional superconductivity one-unit-cell FeSe transport measurement diamagnetic prop-erty

Machine learning-aided atomic structure identification of interfacial ionic hydrates from AFM images

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National Science Review 2023年第7期10卷 114-123页

作者： Binze Tang Yizhi Song Mian Qin Ye Tian Zhen Wei Wu Ying Jiang Duanyun Cao Limei Xu International center for quantum Materials Peking University School of Physics Peking University Institute of Nonequilibrium systems School of Systems Science Beijing Normal University Collaborative Innovation center of quantum Matter CAS center for Excellence in Topological quantum Computation University of Chinese Academy of Sciences Interdisciplinary Institute of Light-Element quantum Materials and Research center for Light-Element Advanced Materials Peking University Beijing Key Laboratory of Environmental Science and Engineering School of Materials Science and Engineering Beijing Institute of Technology Beijing Institute of Technology Chongqing Innovation center

Relevant to broad applied fields and natural processes,interfacial ionic hydrates have been widely studied by using ultrahigh-resolution atomic force microscopy(AFM).However,the complex relationship between the AFM signal and the investigated system makes it difficult to determine the atomic structure of such a complex system from AFM images *** machine learning,we achieved precise identification of the atomic structures of interfacial water/ionic hydrates based on AFM images,including the position of each atom and the orientations of water mole ***,it was found that structure prediction of ionic hydrates can be achieved cost-effectively by transfer learning using neural network trained with easily available interfacial water ***,this work provides an efficient and economical methodology that not only opens up avenues to determine atomic structures of more complex systems from AFM images,but may also help to interpret other scientific studies involving sophisticated experimental results.

关键词： machine learning transfer learning atomic force microscopy atomic scale structure identification interfacial ion hydrates

Narrow Waveguide Based on Ferroelectric Domain Wall

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Chinese Physics Letters 2021年第8期38卷 121-125页

作者： Gongzheng Chen Jin Lan Tai Min Jiang Xiao Department of Physics and State Key Laboratory of Surface Physics Fudan UniversityShanghai 200433China Institute for Nanoelectronics Devices and quantum Computing Fudan UniversityShanghai 200433China center for Joint quantum Studies and Department of Physics School of ScienceTianjin UniversityTianjin 300072China center for spintronics and quantum System State Key Laboratory for Mechanical Behavior of MaterialsSchool of Materials Science and EngineeringXi'an Jiaotong UniversityXi'an 710049China Shanghai Research center for quantum Sciences Shanghai 201315China

Ferroelectric materials are spontaneous symmetry breaking systems that are characterized by ordered electric *** to its ferromagnetic counterpart,a ferroelectric domain wall can be regarded as a soft interface separating two different ferroelectric *** we show that two bound state excitations of electric polarization(polar wave),or the vibration and breathing modes,can be hosted and propagate within the ferroelectric domain *** particular,the vibration polar wave has zero frequency gap,thus is constricted deeply inside ferroelectric domain wall,and can even propagate in the presence of local *** ferroelectric domain wall waveguide as demonstrated here offers a new paradigm in developing ferroelectric information processing units.

关键词： polarization waveguide ferroelectric