检索结果-南通市图书馆

Scaling dependence of memory windows and different carrier charging behaviors in Si nanocrystal nonvolatile memory devices

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics B 2016年第9期25卷 518-522页

作者：于杰陈坤基马忠元张鑫鑫江小帆吴仰晴黄信凡 Shunri Oda State Key Laboratory of Solid State Microstructures and School of Electronic Science and Engineering Nanjing University quantum nanoelectronics research center Tokyo Institute of Technology

Based on the charge storage mode,it is important to investigate the scaling dependence of memory performance in silicon nanocrystal（Si-NC） nonvolatile memory（NVM） devices for its scaling down *** this work,we made eight kinds of test key cells with different gate widths and lengths by 0.13-μm node complementary metal oxide semiconductor（CMOS） *** is found that the memory windows of eight kinds of test key cells are almost the same of about1.64 V @ ±7 V/1 ms,which are independent of the gate area,but mainly determined by the average size（12 nm） and areal density（1.8×10^（11）/cm^2） of *** program/erase（P/E） speed characteristics are almost independent of gate widths and ***,the erase speed is faster than the program speed of test key cells,which is due to the different charging behaviors between electrons and holes during the operation ***,the data retention characteristic is also independent of the gate *** findings are useful for further scaling down of Si-NC NVM devices to improve the performance and on-chip integration.

关键词： silicon nanocrystals nonvolatile memory scaling dependence different charging behaviors

The detection, extraction and parameter estimation of extreme-mass-ratio inspirals with deep learning

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 86-96页

作者： Qianyun Yun Wen-Biao Han Yi-Yang Guo He Wang Minghui Du Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences Shanghai Astronomical Observatory Chinese Academy of Sciences School of Physics and Astronomy Shanghai Jiao Tong University School of Astronomy and Space Science University of Chinese Academy of Sciences Taiji Laboratory for Gravitational Wave Universe (Beijing/Hangzhou) University of Chinese Academy of Sciences Lanzhou center for Theoretical Physics Key Laboratory of Theoretical Physics of Gansu Province Key Laboratory of Quantum Theory and Applications of MoE Lanzhou University Institute of Theoretical Physics & research center of Gravitation Lanzhou University International Centre for Theoretical Physics Asia-Pacific (ICTP-AP) University of Chinese Academy of Sciences (UCAS) center for Gravitational Wave Experiment National Microgravity Laboratory Institute of Mechanics Chinese Academy of Sciences

One of the primary goals of space-borne gravitational wave detectors is to detect and analyze extreme-mass-ratio inspirals(EMRIs). This task is particularly challenging because EMRI signals are complex, lengthy, and faint. In this work, we introduce a2-layer convolutional neural network(CNN) approach to detect EMRI signals for space-borne detectors, achieving a true positive rate(TPR) of 96.9% at a 1% false positive rate(FPR) for signal-to-noise ratio(SNR) from 50 to 100. Especially, the key intrinsic parameters of EMRIs such as the mass, spin of the supermassive black hole(SMBH) and the initial eccentricity of the orbit can also be inferred directly by employing a neural network. The mass and spin of the SMBH can be determined at 99% and 92% respectively. This will greatly reduce the parameter spaces and computing cost for the following Bayesian parameter *** model also has a low dependency on the accuracy of the waveform model. This study underscores the potential of deep learning methods in EMRI data analysis, enabling the rapid detection of EMRI signals and efficient parameter estimation.

关键词： gravitational wave EMRIs deep-learing

A hybrid quantum-classical Hamiltonian learning algorithm

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2023年第2期66卷 295-296页

作者： Youle WANG Guangxi LI Xin WANG center for quantum Software and Information University of Technology Sydney Institute for quantum Computing Baidu Research

Dear editor,Hamiltonian learning is a central task in studying quantum physics systems and the experimental realization of quantum computers. It can be applied to predict the quantum system’s locality and describe the effective interactions between particles, which plays a crucial role in quantum technology, such as quantum simulation and adiabatic quantum computation. In many-body physics,

关键词： Hamiltonians

Narrow Waveguide Based on Ferroelectric Domain Wall

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

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

Theory of the magnon Kerr effect in cavity magnonics

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2019年第8期62卷 93-103页

作者： GuoQiang Zhang YiPu Wang JianQiang You quantum Physics and quantum Information Division Beijing Computational Science Research Center 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 Instrumentation Zhejiang University

We develop a theory for the magnon Kerr effect in a cavity magnonics system, consisting of magnons in a small yttrium iron garnet(YIG) sphere strongly coupled to cavity photons, and use it to study the bistability in this hybrid system. To have a complete picture of the bistability phenomenon, we analyze two different cases in driving the cavity magnonics system, i.e.,directly pumping the YIG sphere and the cavity, respectively. In both cases, the magnon frequency shifts due to the Kerr effect exhibit a similar bistable behavior but the corresponding critical powers are different. Moreover, we show how the bistability of the system can be demonstrated using the transmission spectrum of the cavity. Our results are valid in a wide parameter regime and generalize the theory of bistability in a cavity magnonics system.

关键词： magnon Kerr effect cavity magnonics bistability hybrid system

Electronic transport properties of Co cluster-decorated graphene

在线全文

学校读者我要写书评

暂无评论

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

A brief review of thermal transport in mesoscopic systems from nonequilibrium Green’s function approach

在线全文

学校读者我要写书评

暂无评论

Frontiers of physics 2021年第4期16卷 91-108页

作者： Zhi-Zhou Yu Guo-Huan Xiong Li-Fa Zhang NNU-SULI Thermal Energy research center(NSTER)&center for quantum Transport and Thermal Energy

With the rapidly increasing integration density and power density in nanoscale electronic devices,the thermal management concerning heat generation and energy harvesting becomes quite *** phonon is the major heat carrier in semiconductors,thermal transport due to phonons in mesoscopic systems has attracted much *** quantum transport studies,the nonequilibrium Green’s function(NEGF)method is a versatile and powerful tool that has been developed for several *** this review,we will discuss theoretical investigations of thermal transport using the NEGF approach from two *** the aspect of phonon transport,the phonon NEGF method is briefly introduced and its applications on thermal transport in mesoscopic systems including one-dimensional atomic chains,multi-terminal systems,and transient phonon transport are *** the aspect of thermoelectric transport,the caloritronic effects in which the charge,spin,and valley degrees of freedom are manipulated by the temperature gradient are *** time-dependent thermoelectric behavior is also presented in the transient regime within the partitioned scheme based on the NEGF method.

关键词： thermal transport nonequilibrium Green’s function

Lattice-based access authentication scheme for quantum communication networks

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2024年第12期67卷 311-317页

作者： Min WANG Gui-Lu LONG Beijing Academy of quantum Information Sciences State Key Laboratory of Low-dimensional quantum Physics and Department of Physics Tsinghua University Frontier Science center for quantum Information Beijing National research center for Information Science and Technology

Access authentication scheme plays a foundational role in ensuring the security of communication networks. However, an access authentication scheme with high security and efficiency is still lacking in quantum communication networks. In this paper, we propose a lattice-based access authentication scheme for quantum communication networks in the manner of real-time interaction with the network control center,which could achieve properties of mutual authentication, conditional anonymity, data confidentiality, unforgeability, undeniability, and data integrity. We utilize the digital signature algorithm CRYSTALS-Dilithium and the key-establishment algorithm CRYSTALS-KYBER, both of which have been selected for standardization by the National Institute of Standards and Technology, to realize secure access authentication for users of the quantum communication networks. Specifically, in the quantum secure direct communication network, key-establishment is replaced by the verification of signatures encoded in quantum states. Our results demonstrate the feasibility of establishing a quantum-secure communication network.

关键词： quantum communication quantum network access authentication post-quantum cryptography network control center

同方期刊数据库

Superfluidity of Bose Einstein condensates in ultracold atomic gases

在线全文

学校读者我要写书评

暂无评论

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