共查询到20条相似文献,搜索用时 78 毫秒
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在静电场中,零电势点位置的确定,对电势计算的方便与否起着致关重要的作用.下面就4种情况,简述零电势点位置的确定及相应电势的计算公式.1 点电荷电场中各点电势的计算 例1 设一带电量为Q的点电荷,放在相对电容率为εT的无限大均匀电介质中,求空间各点的电势. 相似文献
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对于掺铁铌酸锂晶体中不同全息记录配置下的磁光折变效应做了比较系统的理论分析,给出了铌酸锂晶体所有的磁光生伏打非零张量元. 详细计算并给出了不同全息纪录配置下的所有体光生伏打、磁光生伏打电流的解析形式. 理论结果表明,由于磁光生伏打效应引起了光激发电流的变化,所以对于每种配置全息光栅的衍射效率都会受到外加磁场的影响;对于不同的全息记录配置,磁场对铌酸锂晶体光折变非线性性质的影响也不同.讨论了一种确定特定张量元的方法.
关键词:
磁光生伏打
磁光折变效应
光生伏打 相似文献
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不等位电势是霍尔式传感器产生零位误差的主要因素.在霍尔式传感器的直流激励特性实验中霍尔元件处于梯度磁场中,但是磁场强度未知,因此无法确定磁场强度为零的位置.当采用交流激励时,通过调节霍尔元件在磁场中的位置,使输出的最小电势便是不等位电势,此时便可通过补偿桥路进行补偿. 相似文献
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光与物质相互作用可以产生各种光学现象,其中光电效应是非常重要的现象之一.文中集中回顾了文章作者在钙钛矿氧化物异质结的光电效应研究中的进展.在钙钛矿氧化物异质结中,分别观测到了传统的纵向光电效应和反常的横向光电效应,并通过对含时的漂移-扩散方程的自洽求解,从理论上分别揭示了钙钛矿氧化物异质结纵向和横向光电效应的动态过程.文章首先介绍了钙钛矿氧化物异质结纵向光电效应的研究进展,接着概述了钙钛矿氧化物异质结横向光电效应研究的进展.最后对氧化物异质结的纵向和横向光电效应的潜在应用前景进行展望. 相似文献
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P. K. Kashkarov E. A. Konstantinova A. B. Matveeva V. Yu. Timoshenko 《Applied Physics A: Materials Science & Processing》1996,62(6):547-551
Spectral and kinetic dependencies of photovoltaic effects in porous silicon-crystal substrate structures have been studied. Both as-prepared and aged in air samples were used. It is shown for the first time that besides the photovoltage component connected with a depleted region in the silicon substrate at the interface with the porous layer there is a photovoltage due to porous silicon itself. It is established that the electron states with the relaxation time about several minutes are located on the pores surface. The properties of these states changed with the thermal annealing of structures. The superslow hole traps with a relaxation time of about several hours were registered in the aged samples. These traps are located in the oxide on the silicon skeleton surface of the porous silicon. An energy diagram based on the data is suggested that explains the appearance of photovoltaic effects in the investigated structures. 相似文献
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Shchepetilnikov A. V. Khisameeva A. R. Nefyodov Yu. A. Kukushkin I. V. 《JETP Letters》2019,110(9):599-602
JETP Letters - The microwave-induced photovoltage in two-dimensional electron systems in an AlAs quantum well and a ZnO/MgZnO heterojunction under the conditions of the quantum Hall effect is... 相似文献
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S.C Dahlberg 《Surface science》1976,60(1):231-238
The transient photovoltage signals of n-type InP(100) have been studied by the retarding potential electron beam technique and are a sensitive function of several experimental parameters. The photovoltage decreases as the duration of the light exposure, and/or the intensity of the light is decreased. The photovoltage decreases sharply at energies less than the bandgap energy, which is temperature dependent, and also shows considerable structure at energies above the bandgap energy. The photovoltage is also sensitive to changes in the surface composition. Both the photovoltage and the work function decrease sharply after Ar bombardment. 相似文献
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According to the p-n junction model of Shockley,the relationship between the equilibrium carrier concentrations of n-type and p-type semiconductors on the edges of the depletion region of a p-n junction solar cell is analysed.The calculation results show that the photovoltage can exceed the built-in voltage for a special kind of heterojunction solar cell.When the photovoltage exceeds the built-in voltage under illumination,the dark current and the photocurrent are impeded by the peak of voltage barrier at the interface and the expression of the total I-V characteristic is given. 相似文献
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S.C Dahlberg 《Surface science》1976,59(1):83-96
The work function and photovoltage of Ar bombarded and thermally annealed surfaces of GaAs have been examined with the retarding potential electron beam technique. The I–V curve obtained by this method is found to fit the theoretically prodicted dependence. The shift of the I–V curve under illumination is related to the photovoltage of the sample. The shift of the I–V curve during the adsorption of oxygen can be explained by a first-order-kinetics dependence of the adsorption on oxygen. The dependence of the photovoltage on light intensity is found to deviate from that measured with the Kelvin technique. The photovoltage is observed to fall off at photon energies below the bandgap energy. At energies above the bandgap, there is structure which is possibly due to excitons. Below the bandgap the photovoltage is sensitive to surface conditions and is much lower for an uncleaned sample. 相似文献
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An Al-doped ZnO/p-Si heterojunction is fabricated by a laser molecular beam epitaxy technique. The abnormally high ideality factors (n 〉〉 2) of the prepared heterojunction are observed in the interim bias voltage range. A theoretical model is proposed to understand the much higher ideality factor of the special heterojunction diode. The ZnO:Al film shows metal-like conductivity with the electrical resistivity about 6.56 × 10-4 Ω·cm at room temperature. The temperature dependence of the photovoltage indicates that the photovoltaic effect of the Al-doped ZnO based heterojunction can be changed by the intrinsic metal-semiconductor transition at 120 K. 相似文献
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通过求解一维稳态少子扩散方程,推导了含有后界面复合速率和发射层厚度的透射式GaAs光电阴极表面光电压谱理论方程.通过对发射层厚度分别为1.6 μm和2.0 μm,掺杂浓度为1×1019 cm-3的GaAs透射式阴极样品测试,理论曲线和实验曲线基本一致.通过引入表面光电压谱积分灵敏度公式,仿真探讨了表面光电压谱在一定体材料参量条件下,积分灵敏度受发射层厚度的影响|发现在体材料参量一定条件下,透射式GaAs光电阴极具有最佳厚度,同时最佳厚度受后界面复合速率的影响更大,同时GaAlAs窗口层也能很好降低发射层后界面复合速率. 相似文献