检索结果-南通市图书馆

Chinese Physics B 2015年第2期24卷 403-408页

作者：熊永臣王为忠杨俊涛黄海铭 School of Science Hubei University of Automotive Technology(HUAT) Department of Physics Wuhan University Key Laboratory of Artificial Micro-and Nano-structures of Ministry of Education

The quantum phase transition and the electronic transport in a triangular quantum dot system are investigated using the numerical renormalization group *** concentrate on the interplay between the interdot capacitive coupling V and the interdot tunnel coupling *** small t,three dots form a local spin *** t increases,due to the competition between V and t,there exist two first-order transitions with phase sequence spin-doublet-magnetic frustration phase-orbital spin *** t is absent,the evolutions of the total charge on the dots and the linear conductance are of the typical coulomb-blockade features with increasing gate *** for sufficient t,the antiferromagnetic spin correlation between dots is enhanced,and the conductance is strongly suppressed for the bonding state is almost doubly occupied.

关键词： quantum phase transition coulomb blockade effect triangular quantum dots strongly correlated system

coulomb blockade effect IN SELF-ASSEMBLED GOLD QUANTUM DOTS

在线全文

学校读者我要写书评

暂无评论

China Particuology 2004年第4期2卷 174-176页

作者： Shu-FenHu Ru-LingYeh Ru-ShiLiu DepartmtentofChemistry.TaiwanUniversity Taipei106China NanoDeviceLaboratories Hsinchu300China

Nanometer-scale Au quantum dots have been assembled on SiO2 by controlling the reaction of raw materials to form a citrate Au sol and an aminosilane/dithiol-treated patterned Si wafer. The detailed formation mechanism has been studied. Three gold colloidal particles (15 nm), aligned in a chain to form a one-dimensional current path, was bridged across an 80-nm gap between source and drain metal electrodes. The device exhibited a coulomb blockade effect at 33 K.

关键词： quantum dots coulomb blockade effect gold

Preparation of size controllable copper nanocrystals for nonvolatile memory applications

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2010年第10期19卷 593-596页

作者：王利孙红芳周惠华朱静 Beijing National Center for Electron Microscopy Department of Materials Science and Engineering Tsinghua University

A method of fabricating Cu nanocrystals embedded in SiO2 dielectric film for nonvolatile memory applications by magnetron sputtering is introduced in this paper. The average size and distribution density of Cu nanocrystal grains are controlled by adjusting experimental parameters. The relationship between nanocrystal floating gate micro-structure and its charge storage capability is also discussed theoretically.

关键词： nanocrystal grain nonvolatile memory coulomb blockade effect magnetron sputtering

Theoretical investigation on tunneling magnetoresistance in ferromagnetic/anti-ferromagnetic core/shell system

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2012年第11期55卷 2038-2041页

作者： YANG YanMin HUANG ZhiGao College of Physics and Energy Fujian Normal UniversityFuzhou 350007China

Based on Monte Carlo simulations,the effect of structural configuration on the hysteresis behavior and tunneling magnetoresistance(TMR) of composite nanoparticles with ferromagnetic(FM) core/anti-ferromagnetic(AFM) shell is *** simulated results indicate that the coercive field(H c) of composites increases with the decreasing ratio of core-radius(r core) to shell-radius(r shell).When the ratio of r shell to r core is approaching 4:3,H c decreases with increasing AFM *** addition,TMR is found to increase with the decreasing ratio of r core to r shell,resulting from the enhancement of resistance changes in disordered AFM shell.

关键词： tunneling magnetoresistance nano-particle arrays coulomb blockade effect spin-dependent scattering Monte Carlosimulation

effect of Nano Silver Modification on the Dielectric Properties of Ag@TiO_(2)/PVDF Composites

在线全文

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(Materials Science) 2021年第3期36卷 303-310页

作者： DAI Jinhang MENG Shunliang YANG Chuntian Lv Wenzhong CHEN Xizi YIN Yuhao LIANG Fei Key Laboratory of Functional Materials for Electronic Information(B) Ministry of EducationHuazhong University of Science and TechnologyWuhan 430074China Wenzhou Institute of Industrial Science Wenzhou 325028China Huawei Technologies Co.Ltd. Shenzhen 518116China

To get a dielectric material with a high dielectric permittivity and suppressed dielectric loss,nano-Ag with a particle size of 20 nm and Ag@TiO_(2)core-shell particles with diameters of approximately 70-120 nm were embedded in polyvinylidene fluoride(PVDF)to fabricate nano-Ag/Ag@TiO_(2)/PVDF *** being modified by nano-Ag with 3 vol%optimal amount,the relative permittivity(ε_r)at 100 Hz of 50 vol%Ag@TiO_(2)/PVDF composites was 61,and the dielectric loss can be suppressed to 0.04,almost 96.4%lower than that of unmodified composites,and a higher frequency stability of bothε_r and loss has also been *** underlying mechanism of the reduced loss was attributed to Maxwell-Wagner polarization and the coulomb blockade effect caused by the introduction of a small amount of nano-Ag,which will block the movement of electrons between metal nanoparticles and *** space charge polarization and conductance loss are weakened at lower and higher Ag@TiO_(2)filling ratios,respectively,thus leading to a very low loss of the composites.

关键词： polymer composites dielectric properties AC impedance spectrum Ag@TiO_(2)/PVDF coulomb blockade effect