In this paper, method combined vapor transportation with in-situ chemical reaction is employed to synthesize Cu(TCNQ) nanowires. The typical diameter of nanowires is 50-500 nm with high uniformity. The electrical swit...In this paper, method combined vapor transportation with in-situ chemical reaction is employed to synthesize Cu(TCNQ) nanowires. The typical diameter of nanowires is 50-500 nm with high uniformity. The electrical switching characteristics of single nanowire are observed. The ON-OFF resistance ratio for switching reaches 10~4. The investigation reveals a linear relationship between the switching threshold and the spacing between the two electrodes. The temporal response of the switching process is 30 ns and the switch exhibits good reproducibility. The collapse of the nanowire under the condition of current surge is also discussed. It is believed that the Cu(TCNQ) nanowire could be promising for applications in nanoelectronics.展开更多
The cadmium ferrite and 5 % rare-earth ions（Sm^3＋, Y^3＋, and La^3＋） added Cd ferrites were synthesized by oxalate co-precipitation method and characterized by X-ray diffraction（XRD）, Fourier transform infrared ...The cadmium ferrite and 5 % rare-earth ions（Sm^3＋, Y^3＋, and La^3＋） added Cd ferrites were synthesized by oxalate co-precipitation method and characterized by X-ray diffraction（XRD）, Fourier transform infrared spectroscopy（FT-IR）, and scanning electron microscope（SEM） techniques. All ferrite samples under investigation exhibit current-controlled negative resistance type I–E characteristics at room temperature. The required electrical-switching field in cadmium ferrite is higher than that for 5 % Sm^3＋, Y^3＋, and La^3＋added cadmium ferrites. The5% addition of Sm^3＋, Y^3＋, and La^3＋ in cadmium ferrite is found to decrease the grain size in this ferrite. This decrement in the grain size makes the required switching field to decrease in cadmium ferrite. No aging effect for electrical switching is observed in these ferrites.展开更多
We report that fully transparent resistive random access memory （TRRAM） devices based on ITO/TiO2/ITO sandwich structure, which are prepared by the method of RF magnetron sputtering, exhibit excellent switching stab...We report that fully transparent resistive random access memory （TRRAM） devices based on ITO/TiO2/ITO sandwich structure, which are prepared by the method of RF magnetron sputtering, exhibit excellent switching stability. In the visible region （400 800 nm in wavelength） the TRRAM device has a transmittance of more than 80%. The fabricated TRRAM device shows a bipolar resistance switching behaviour at low voltage, while the retention test and rewrite cycles of more than 300,000 indicate the enhancement of switching capability. The mechanism of resistance switching is further explained by the forming and rupture processes of the filament in the TiO2 layer with the help of more oxygen vacancies which are provided by the transparent ITO electrodes.展开更多
In this paper, the effect of electric boundary conditions on Mode I crack propagation in ferroelectric ceramics is studied by using both linear and nonlinear piezoelectric fracture mechanics. In linear analysis, imper...In this paper, the effect of electric boundary conditions on Mode I crack propagation in ferroelectric ceramics is studied by using both linear and nonlinear piezoelectric fracture mechanics. In linear analysis, impermeable cracks under open circuit and short circuit are analyzed using the Stroh formalism and a rescaling method. It is shown that the energy release rate in short circuit is larger than that in open circuit. In nonlinear analysis, permeable crack conditions are used and the nonlinear effect of domain switching near a crack tip is considered using an energy-based switching criterion proposed by Hwang et al.（Acta Metal. Mater.,1995）. In open circuit, a large depolarization field induced by domain switching makes switching much more diffcult than that in short circuit. Analysis shows that the energy release rate in short circuit is still larger than that in open circuit, and is also larger than the linear result. Consequently,whether using linear or nonlinear fracture analysis, a crack is found easier to propagate in short circuit than in open circuit, which is consistent with the experimental observations of Kounga Njiwa et al.（Eng. Fract. Mech., 2006）.展开更多
In order to solve the problem of vibration bounce caused by the contact between moving and stationary contacts in the process of switching on,two-degree-of-freedom motion differential equation of the contact system is...In order to solve the problem of vibration bounce caused by the contact between moving and stationary contacts in the process of switching on,two-degree-of-freedom motion differential equation of the contact system is established.Genetic algorithm is used to optimize the pull in process of AC contactor.The whole process of contact bounce was observed and analyzed by high-speed photography experiment.The theory and experimental results were very similar.The iron core has collided before the contact is separated,which further aggravates the contact bounce.When the iron core bounces collided again,the bounce of the contact was not affected.During the operation of the contactor,the movement of the moving iron core will cause slight vibration of the system.The contact bounce time and the maximum amplitude are reduced.The research results provide a theoretical basis for further control and reduction of contact bounce.展开更多
Single-molecule electrical and spin switches have been one of the main research focuses in molecular electronics and spintronics because they may form the most important elements for the future information technology,...Single-molecule electrical and spin switches have been one of the main research focuses in molecular electronics and spintronics because they may form the most important elements for the future information technology,thus attracting great attention in the scientific community and witnessing significant progresses benefiting from the combination of physics,chemistry,materials,and engineering.The key issue of constructing single-molecule switches is the development of stimulus-responsive systems that provide bistable or multiple states.In this review,we summarize the recent advances of this field in terms of the external stimulus that induces the switching.A variety of external stimuli,such as light,electric field,magnetic field,mechanical force,and chemical stimulus,have been successfully employed to activate the reversible switching in single-molecule junctions by manipulating molecular structures,conformations,electronic states,and spin states.As a burgeoning field,we finally put forward the challenges in molecular electronics and spintronics that need to be solved,which will initiate intense research.展开更多
Subject Code:F04 With the support by the National Natural Science Foundation of China,a study by the research group led by Prof.Wang Kaiyou(王开友)from the Institute of Semiconductors,Chinese Academy of Sciences demon...Subject Code:F04 With the support by the National Natural Science Foundation of China,a study by the research group led by Prof.Wang Kaiyou(王开友)from the Institute of Semiconductors,Chinese Academy of Sciences demonstrates all-electric and programmable manipulations of ferromagnetic bits without external展开更多
In this letter, we propose a voltage-controlled optical filter based on electrowetting. The device is made of a transparent cubic cell filled with two immiscible liquids having three indium tin oxide electrodes fabric...In this letter, we propose a voltage-controlled optical filter based on electrowetting. The device is made of a transparent cubic cell filled with two immiscible liquids having three indium tin oxide electrodes fabricated on the bottom substrate of the cell. A conductive droplet carrying a color filter is placed on the ITO electrode and the surrounding liquid is density-matched silicone oil. Under zero bias, the droplet is placed in the middle of tile substrate and white light passes through the filter and we can see red light on the screen. When a voltage is applied to the device, the filter moves with the liquid based on electrowetting effect, we can see the white light on the screen. Due to the movement of the liqnid, our device functions as an optical switcher. The switch trine of the device is -70 ms. The proposed device has a wide application in optical communication. electronic display, and optical switch.展开更多
Antiferromagnetic (AFM) materials have attracted wide attention in spin-orbit torque (SOT)-based spintronic due to its abundant spin-dependent properties and unique advantage of immunity against external field perturb...Antiferromagnetic (AFM) materials have attracted wide attention in spin-orbit torque (SOT)-based spintronic due to its abundant spin-dependent properties and unique advantage of immunity against external field perturbations.To act as the charge-to-spin conversion source in energy-saving spintronic devices,it is of great importance for the AFM material to possess a large spin torque efficiency(ξDL).In this work,using the spin torque ferromagnetic resonance (ST-FMR) technique and a Mn2Au/Ni Fe(Py) bilayer system,we systemically study the ξDLof AFM Mn2Au films with different crystal structures.Compared with polycrystalline Mn2Au with effective ξDL<0.051,we show a much larger ξDLof~0.333 in single-crystal Mn2Au,which arises from the large spin Hall conductivity instead of electrical resistivity.Moreover,with a further contribution of interfacial effects,the effective ξDLof single-crystalline Mn2Au/Py system increases to 0.731,which is more than two times larger than the value of ~0.22 reported for the Mn2Au/CoFeB system.By utilizing the largeξDLof Mn2Au in a perpendicularly magnetized Mn Ga/Mn2Au system,energy-efficient deterministic magnetization switching with a current density at ~10^(6)A cm^(-2)is achieved.Our results reveal a significant potential of Mn2Au as an efficient SOT source and shed light on its application in future AFM material-based SOT integration technology.展开更多
With the support by the National Natural Science Foundation of China,the research team led by Prof.Guo Xuefeng(郭雪峰)at the College of Chemistry and Molecular Engineering,Peking University,realized the first fully-re...With the support by the National Natural Science Foundation of China,the research team led by Prof.Guo Xuefeng(郭雪峰)at the College of Chemistry and Molecular Engineering,Peking University,realized the first fully-reversible two-mode single-molecule electrical switch,which was published in Science(2016,352:1443—1445).展开更多
基金financial support from Shanghai Science and Technology Development Fund(No.0752nm016)Shanghai Leading Academic Development Project(No.B113)
文摘In this paper, method combined vapor transportation with in-situ chemical reaction is employed to synthesize Cu(TCNQ) nanowires. The typical diameter of nanowires is 50-500 nm with high uniformity. The electrical switching characteristics of single nanowire are observed. The ON-OFF resistance ratio for switching reaches 10~4. The investigation reveals a linear relationship between the switching threshold and the spacing between the two electrodes. The temporal response of the switching process is 30 ns and the switch exhibits good reproducibility. The collapse of the nanowire under the condition of current surge is also discussed. It is believed that the Cu(TCNQ) nanowire could be promising for applications in nanoelectronics.
基金financially supported by the Major Research Project of University Grants Commission, New Delhi, India (No. F.No. 36-212/2008)
文摘The cadmium ferrite and 5 % rare-earth ions（Sm^3＋, Y^3＋, and La^3＋） added Cd ferrites were synthesized by oxalate co-precipitation method and characterized by X-ray diffraction（XRD）, Fourier transform infrared spectroscopy（FT-IR）, and scanning electron microscope（SEM） techniques. All ferrite samples under investigation exhibit current-controlled negative resistance type I–E characteristics at room temperature. The required electrical-switching field in cadmium ferrite is higher than that for 5 % Sm^3＋, Y^3＋, and La^3＋added cadmium ferrites. The5% addition of Sm^3＋, Y^3＋, and La^3＋ in cadmium ferrite is found to decrease the grain size in this ferrite. This decrement in the grain size makes the required switching field to decrease in cadmium ferrite. No aging effect for electrical switching is observed in these ferrites.
基金Project supported by the National Basic Research Program of China (Grant No. 2007CB925002)the National High Technology Research and Development Program of China (Grant No. 2008AA031401)and Chinese Academy of Sciences
文摘We report that fully transparent resistive random access memory （TRRAM） devices based on ITO/TiO2/ITO sandwich structure, which are prepared by the method of RF magnetron sputtering, exhibit excellent switching stability. In the visible region （400 800 nm in wavelength） the TRRAM device has a transmittance of more than 80%. The fabricated TRRAM device shows a bipolar resistance switching behaviour at low voltage, while the retention test and rewrite cycles of more than 300,000 indicate the enhancement of switching capability. The mechanism of resistance switching is further explained by the forming and rupture processes of the filament in the TiO2 layer with the help of more oxygen vacancies which are provided by the transparent ITO electrodes.
基金supported by the National Natural Science Foundation of China(11002002 and 11090331)
文摘In this paper, the effect of electric boundary conditions on Mode I crack propagation in ferroelectric ceramics is studied by using both linear and nonlinear piezoelectric fracture mechanics. In linear analysis, impermeable cracks under open circuit and short circuit are analyzed using the Stroh formalism and a rescaling method. It is shown that the energy release rate in short circuit is larger than that in open circuit. In nonlinear analysis, permeable crack conditions are used and the nonlinear effect of domain switching near a crack tip is considered using an energy-based switching criterion proposed by Hwang et al.（Acta Metal. Mater.,1995）. In open circuit, a large depolarization field induced by domain switching makes switching much more diffcult than that in short circuit. Analysis shows that the energy release rate in short circuit is still larger than that in open circuit, and is also larger than the linear result. Consequently,whether using linear or nonlinear fracture analysis, a crack is found easier to propagate in short circuit than in open circuit, which is consistent with the experimental observations of Kounga Njiwa et al.（Eng. Fract. Mech., 2006）.
基金Natural Science Foundation of Shaanxi Province(No.2011J2009)。
文摘In order to solve the problem of vibration bounce caused by the contact between moving and stationary contacts in the process of switching on,two-degree-of-freedom motion differential equation of the contact system is established.Genetic algorithm is used to optimize the pull in process of AC contactor.The whole process of contact bounce was observed and analyzed by high-speed photography experiment.The theory and experimental results were very similar.The iron core has collided before the contact is separated,which further aggravates the contact bounce.When the iron core bounces collided again,the bounce of the contact was not affected.During the operation of the contactor,the movement of the moving iron core will cause slight vibration of the system.The contact bounce time and the maximum amplitude are reduced.The research results provide a theoretical basis for further control and reduction of contact bounce.
基金National Key R&D Program of China,Grant/Award Number:2017YFA0204901National Natural Science Foundation of China,Grant/Award Numbers:21727806,21933001Natural Science Foundation of Beijing,Grant/Award Number:Z181100004418003。
文摘Single-molecule electrical and spin switches have been one of the main research focuses in molecular electronics and spintronics because they may form the most important elements for the future information technology,thus attracting great attention in the scientific community and witnessing significant progresses benefiting from the combination of physics,chemistry,materials,and engineering.The key issue of constructing single-molecule switches is the development of stimulus-responsive systems that provide bistable or multiple states.In this review,we summarize the recent advances of this field in terms of the external stimulus that induces the switching.A variety of external stimuli,such as light,electric field,magnetic field,mechanical force,and chemical stimulus,have been successfully employed to activate the reversible switching in single-molecule junctions by manipulating molecular structures,conformations,electronic states,and spin states.As a burgeoning field,we finally put forward the challenges in molecular electronics and spintronics that need to be solved,which will initiate intense research.
文摘Subject Code:F04 With the support by the National Natural Science Foundation of China,a study by the research group led by Prof.Wang Kaiyou(王开友)from the Institute of Semiconductors,Chinese Academy of Sciences demonstrates all-electric and programmable manipulations of ferromagnetic bits without external
基金supported by the National Natural Science Foundation of China(Nos.61225022 and 61320106015)the National "973" Program of China(No.2013CB328802)+1 种基金the National "863" Program of China(No.2012AA011901)the Research Program of Sichuan Province,China(No.2013TD0002)
文摘In this letter, we propose a voltage-controlled optical filter based on electrowetting. The device is made of a transparent cubic cell filled with two immiscible liquids having three indium tin oxide electrodes fabricated on the bottom substrate of the cell. A conductive droplet carrying a color filter is placed on the ITO electrode and the surrounding liquid is density-matched silicone oil. Under zero bias, the droplet is placed in the middle of tile substrate and white light passes through the filter and we can see red light on the screen. When a voltage is applied to the device, the filter moves with the liquid based on electrowetting effect, we can see the white light on the screen. Due to the movement of the liqnid, our device functions as an optical switcher. The switch trine of the device is -70 ms. The proposed device has a wide application in optical communication. electronic display, and optical switch.
基金supported by the Agency for Science,Technology and Research (A*STAR) of Singapore (A1983c0036)the Singapore Ministry of Education (MOE2018-T2-2043)A*STAR IAF-ICP 11801E0036。
文摘Antiferromagnetic (AFM) materials have attracted wide attention in spin-orbit torque (SOT)-based spintronic due to its abundant spin-dependent properties and unique advantage of immunity against external field perturbations.To act as the charge-to-spin conversion source in energy-saving spintronic devices,it is of great importance for the AFM material to possess a large spin torque efficiency(ξDL).In this work,using the spin torque ferromagnetic resonance (ST-FMR) technique and a Mn2Au/Ni Fe(Py) bilayer system,we systemically study the ξDLof AFM Mn2Au films with different crystal structures.Compared with polycrystalline Mn2Au with effective ξDL<0.051,we show a much larger ξDLof~0.333 in single-crystal Mn2Au,which arises from the large spin Hall conductivity instead of electrical resistivity.Moreover,with a further contribution of interfacial effects,the effective ξDLof single-crystalline Mn2Au/Py system increases to 0.731,which is more than two times larger than the value of ~0.22 reported for the Mn2Au/CoFeB system.By utilizing the largeξDLof Mn2Au in a perpendicularly magnetized Mn Ga/Mn2Au system,energy-efficient deterministic magnetization switching with a current density at ~10^(6)A cm^(-2)is achieved.Our results reveal a significant potential of Mn2Au as an efficient SOT source and shed light on its application in future AFM material-based SOT integration technology.
文摘With the support by the National Natural Science Foundation of China,the research team led by Prof.Guo Xuefeng(郭雪峰)at the College of Chemistry and Molecular Engineering,Peking University,realized the first fully-reversible two-mode single-molecule electrical switch,which was published in Science(2016,352:1443—1445).
