三维电子气(Three Dimensional Electron Gas,3DEG)是极化掺杂场效应晶体管(Polarization-doped Field Effect Transistor,PolFET)优秀性能的关键所在,但目前未见三维电子气相关的定量理论工作。提出三维电子气的定量理论,基于PolFET中...三维电子气(Three Dimensional Electron Gas,3DEG)是极化掺杂场效应晶体管(Polarization-doped Field Effect Transistor,PolFET)优秀性能的关键所在,但目前未见三维电子气相关的定量理论工作。提出三维电子气的定量理论,基于PolFET中的渐变Al组分铝镓氮(Aluminum Gallium Nitride,AlGaN)层的极化效应定量研究,计算体极化电荷分布,结合空间电荷分析提出AlGaN层的耗尽近似和中性近似,引入费米-狄拉克统计、能带电势关系等物理关系,建立求解耗尽区宽度的方程组,定义其边界条件与边界近似,并给出求解耗尽区宽度的数值解法和方程解析解(最大相对误差均不超过3%)。展开更多
N-Doped carbon materials have shown great potential in energy-related areas,but well-controlled doping of nitrogen and components along with fine-construction of multidimensional porous architectures remains a great i...N-Doped carbon materials have shown great potential in energy-related areas,but well-controlled doping of nitrogen and components along with fine-construction of multidimensional porous architectures remains a great issue.Herein,we demonstrate a temperature-directed strategy to fabricate nitrogen-rich three-dimensional(3D)porous carbon composites with nanosheets and hollow spheres for efficient supercapacitors.展开更多
Magnetic Monopole SearchesIsolated supermassive monopole candidate events have not been confirmed. The most sensitive experiments obtain negative results.
We propose a wavelength selective diffraction using reflectors placed on three-dimensional grid cross points. Different wavelengths are separated into spots distributed in two-dimensional plane. Compact device with hi...We propose a wavelength selective diffraction using reflectors placed on three-dimensional grid cross points. Different wavelengths are separated into spots distributed in two-dimensional plane. Compact device with high port counts is attainable.展开更多
A three-dimensional composite(N-PC/Ti_(3)C_(2))of MXene nanosheets and porous carbon was prepared by a facile self-sacrificing template method and further served as a sulfur host for lithium-sulfur batteries.The coexi...A three-dimensional composite(N-PC/Ti_(3)C_(2))of MXene nanosheets and porous carbon was prepared by a facile self-sacrificing template method and further served as a sulfur host for lithium-sulfur batteries.The coexistence of nitrogen-doped porous carbon and MXene nanosheets endowed the composite with a large specific area,a 3D structure,a conductive network and strong physical and chemical doubleadsorption of polysulfides.Furthermore,the sulfur content of the N-PC/Ti_(3)C_(2)composite was high:up to 80%.As the cathode material of lithium-sulfur batteries,the S@N-PC/Ti_(3)C_(2)electrode exhibited a long cycle life with a slow fading rate of 0.04%per cycle over 800 cycles.展开更多
文摘三维电子气(Three Dimensional Electron Gas,3DEG)是极化掺杂场效应晶体管(Polarization-doped Field Effect Transistor,PolFET)优秀性能的关键所在,但目前未见三维电子气相关的定量理论工作。提出三维电子气的定量理论,基于PolFET中的渐变Al组分铝镓氮(Aluminum Gallium Nitride,AlGaN)层的极化效应定量研究,计算体极化电荷分布,结合空间电荷分析提出AlGaN层的耗尽近似和中性近似,引入费米-狄拉克统计、能带电势关系等物理关系,建立求解耗尽区宽度的方程组,定义其边界条件与边界近似,并给出求解耗尽区宽度的数值解法和方程解析解(最大相对误差均不超过3%)。
基金financial support of this research from the National Natural Science Foundation of China(51779065 and 51579057)the State Key Laboratory of Urban Water Resource and Environment,Harbin Institute of Technology(2019DX11).
文摘N-Doped carbon materials have shown great potential in energy-related areas,but well-controlled doping of nitrogen and components along with fine-construction of multidimensional porous architectures remains a great issue.Herein,we demonstrate a temperature-directed strategy to fabricate nitrogen-rich three-dimensional(3D)porous carbon composites with nanosheets and hollow spheres for efficient supercapacitors.
文摘Magnetic Monopole SearchesIsolated supermassive monopole candidate events have not been confirmed. The most sensitive experiments obtain negative results.
文摘We propose a wavelength selective diffraction using reflectors placed on three-dimensional grid cross points. Different wavelengths are separated into spots distributed in two-dimensional plane. Compact device with high port counts is attainable.
基金support from the National Natural Science Foundation of China(No.21773188,51802269)Fundamental Research Funds for the Central Universities(XDJK2019AA002,XDJK2019B052)+1 种基金Natural Science Foundation of Chongqing(cstc2018jcyjAX0714)Experimental Technology Research Project of Southwest University(SYJ2019006).
文摘A three-dimensional composite(N-PC/Ti_(3)C_(2))of MXene nanosheets and porous carbon was prepared by a facile self-sacrificing template method and further served as a sulfur host for lithium-sulfur batteries.The coexistence of nitrogen-doped porous carbon and MXene nanosheets endowed the composite with a large specific area,a 3D structure,a conductive network and strong physical and chemical doubleadsorption of polysulfides.Furthermore,the sulfur content of the N-PC/Ti_(3)C_(2)composite was high:up to 80%.As the cathode material of lithium-sulfur batteries,the S@N-PC/Ti_(3)C_(2)electrode exhibited a long cycle life with a slow fading rate of 0.04%per cycle over 800 cycles.
