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Spin correlations in the S = 1 armchair chain Ni_(2)NbBO_(6) as seen from NMR

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Chinese Physics B 2021年第4期30卷 512-517页

作者：曾凯悦马龙徐龙猛田召明凌浪生皮雳 Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions High Magnetic Field LaboratoryChinese Academy of SciencesHefei 230031China Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China School of Physics and Wuhan National High magnetic Field Center Huazhong University of Science and TechnologyWuhan 430074China

We report our nuclear magnetic resonance(NMR) study on the structurally spin chain compound Ni_(2)NbBO_(6) with complex magnetic coupling.The antiferromagnetic transition is monitored by the line splitting resulting from the staggered internal hyperfine field.The magnetic coupling configuration proposed by the first-principle density functional theory(DFT) is supported by NMR spectral analysis.For the spin dynamics,a prominent peak at T~35 K well above the Neel temperature(T_(N)~20 K at μ0 H=10 T) is observed from the spin-lattice relaxation data.As compared with the dc-susceptibility,this behavior indicates an antiferromagnetic coupling with the typical energy scale of ~3 meV.Thus,the Ni_(2)NbBO_(6) compound can be viewed as strongly ferromagnetically coupled armchair spin chains along the crystalline b-axis.These facts place strong constraints on the theoretical model for this compound.

关键词： low-dimensional quantum magnetism magnetic coupling spin excitations nuclear magnetic resonance

维普期刊数据库

Enhancement of magnetism of Zn0.95Co0.05O films by p-type Cu~+ doping

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Progress in Natural Science:Materials International 2011年第1期21卷 31-35页

作者： Wei-chang HAO~(1,5),Jian-jun LI~2,Huai-zhe XU~3,Jia-ou WANG~4,Tian-min WANG~1 1.Center of Materials Physics and Chemistry,Beihang University,Beijing 100083,China 2.Department of Materials Science and Engineering, Anhui University of Science and Technology,Huainan 232001,China 3.Department of Physics,Beihang University,Beijing 100083,China 4.Beijing Synchrotron Radiation Facility,Institute of High Energy Physics, Chinese Academy of Sciences,100049,China 5.Key Laboratory of Micro-nano Measurement,Manipulation and Physics, Ministry of Education,Beihang University,Beijing 100191,China Center of Materials Physics and Chemistry Beihang University Beijing 100083 China Key Laboratory of Micro-nano Measurement Manipulation and Physics Ministry of Education Beihang University Beijing 100191 China Department of Materials Science and Engineering Anhui University of Science and Technology Huainan 232001 China Department of Physics Beihang University Beijing 100083 China Beijing Synchrotron Radiation Facility Institute of High Energy Physics Chinese Academy of Sciences 100049 China

Zn0.95Co0.05O and Zn0.91Co0.05Cu0.04O thin films were fabricated on Si(111) substrate by the reactive magnetron sputtering method at different O-Ar ratios.Detailed characterizations by X-ray diffractometry(XRD),X-ray photo-electronic spectrum(XPS), and electron paramagnetic resonance(EPR) indicate that the doped Cu ions substitute the Zn2+ions in the ZnO lattice.The doped Cu ions are in Cu~+ and Cu2+mixture valence states.The ferromagnetism of the Zn0.91Co0.05Cu0.04O film increases gradually the increasing Cu~+ ions concentration.The results indicate that the increase of ferromagnetism is not owing to the magnetic contribution of Cu~+ ions themselves,but owing to the enhancement of magnetic interaction between Co ions,which suggests that p-type doping of Cu~+ ions plays an important role in mediating the ferromagnetic coupling between Co ions.

关键词： Zn0.95Co0.05O films Zn0.91Co0.05Cu0.04O films magnetic semiconductors magnetic coupling co-doping

Synthesis and properties of the copper(Ⅱ) complexes with stable radical

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Chinese Journal of Chemistry 1998年第5期16卷 436-441页

作者：孙柏旺李苏琪廖代正姜宗慧刘爱俭闫世平王耕霖 Department of Chemistry Nankai University Tianjin 300071 China State Key Laboratory of Coordination Chemistry Nanjing UniversityNanjingJiangsu 210097 China

Four novel copper(Ⅱ) complexes have been synthesized,namely Cu(hfac)2NITPhNO2 (1),Cu(hfac)2NITPhCH3 (2),Cu(pfpr)2NITPhNO2,(3) and Cu(Pfpr)2NITPhCH3 (4),where hfac= hexafluoro-acetylacetonate,pfpr=pentafluoropropionate,NITR.=2-R-4,4,5,5-tetraniethyl-4,5-dihydro-1H-imidazolyl-1-oxyl-3-oxide.(R=4-nitrophenyl,4-methylphenyl).These complexes were rharicter-ized by elemental analyses,IR,electronic spectra and molar conductance.The temperature-dependent magnetic susceptibility of complexes 1 and 3 have been studied in the 4 300 K range,giving I he exchange integral J=10.56 cm-1 for complex 1 and J =-30.9 cm-1 for complex 3.

关键词： Copper(Ⅱ) complexes rlitroxides magnetic coupling

维普期刊数据库

Magnetotransport properties of La0.67Ca0.33MnO3//La0.67Sr0.33MnO3 bilayers

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Chinese Physics B 2005年第9期14卷 1879-1881页

作者：丰家峰赵昆黄延红赵见高韩秀峰詹文山黄康权 Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China Spintronics Laboratory School of Physics Science and Information Technology Liaocheng University Liaocheng 252059 China International Center for Materials Physics Chinese Academy of Sciences Shenyang 110016 China Department of Physics The Chinese University of Hong Kong Hong Kong

The perovskite bilayers La0.67Ca0.33MnO3 （LCMO）（100 nm） / La0.67Sr0.33MnO3（LSMO）（100 nm） and LSMO （100 nm） / LCMO （100 nm） are fabricated by a facing-target sputtering technique. Their transport and magnetic properties are investigated. It is found that the transport properties between them are different obviously due to distinguishable structures, and the different lattice strains in both films result in the difference of metal-to-insulator transition. Only single-step magnetization loop appears in our bilayers from 5K to 320K, and the coercive force of LSMO/LCMO varies irregularly with a minimum ～ 2387A/m which is lower than that of LCMO and LSMO single layer films. The behaviour is explained by some magnetic coupling.

关键词： manganites magnetic coupling bilayer film

Advances in Inductively Coupled Power Transfer Technology for Rail Transit

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CES Transactions on Electrical Machines and Systems 2017年第4期1卷 383-396页

作者： Liming Shi Zhenggang Yin Longbin Jiang Yaohua Li Key Laboratory of Power Electronics and Electric Drive Institute of Electrical EngineeringChinese Academy of SciencesBeijing 100190China

Traditional power supply method for moving electric railway vehicles is based on contact type power collection technology.This sometimes cannot meet the requirements of modern rail transportation.A new wireless power transfer(WPT)technology can offer significant benefits in modern rail transportation particularly in some stringent environments.This paper reviews the status and the development of rail transit power supply technology,and introduces a new challenging technology--inductive power transfer(IPT)technology for rail transit.Tesla established the underpinning of IPT technology and creatively and significantly demonstrated power transfer by using highly resonant tuned coils long time ago.However,only in recent years the IPT technology has been significantly improved including the transfer air-gap length,transfer efficiency,coupling factor,power transfer capability and so on.This is mainly due to innovative semiconductor switches,higher control frequency,better coil designs and high performance material,new track and vehicle construction techniques.Recent advances in IPT for rail transit and major milestones of the developments are summarized in this paper.Some important technical issues such as coupling coil structures,power supply schemes,segmentation switching techniques for long-distance power supply,and bidirectional IPT systems for braking energy feedback are discussed.

关键词： Bidirectional energy transfer inductive power transfer(IPT) magnetic coupling rail transit segmented power supply wireless power transfer(WPT).

magnetic Circuit Design and Analysis Used in magnetic Sealing Drive Device

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Magnetic Circuit Design and Analysis Used in Magnetic Sealin...

Structure Controllable Molecular magnetic Refrigerants and a Symbol Approach to Classify Molecule-Based Magnets

The 2012 International Conference on Advanced Material and Manufacturing Science(ICAMMS 2012)

作者： Dingzhong Tan Ying Qiu Qiming Wang College of Mechanical and Electrical Engineering Harbin Engineering University

according to the requirement of designing the magnetic sealing drive,the magnetic sealing drive torque design and calculation is completedIt is also analyzed the magnetic circuit and the whole structure of the driveThe matching problem of magnet thickness and arc length of magnetic pole surface is analyzedThe research also includes the method to calculate torque of combination of push pull magnetic circuit and method of its power matching calculation and correctionThe magnetic sealing drive is tested and the results show that the design of the magnetic sealing drive complies with the design requirements

关键词： magnetic coupling Drive Seal magnetic Circuit

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Structure Controllable Molecular Magnetic Refrigerants and a...