Resonant Nonlinear Optical Susceptibility: Electroreflectance in the Low-Field Limit
Resonant Nonlinear Optical Susceptibility: Electroreflectance in the Low-Field Limit
复制标题
共振非线性光学磁化率：低场极限下的电反射
DOI：
10.1103/physrevb.5.4022
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发表时间：
1972
影响因子：
3.7
通讯作者：
J. Rowe
中科院分区：
文献类型：
--
作者：
D. Aspnes;J. Rowe
通过类似于描述非线性光学现象的微扰处理，发展了电场对固体介电函数的影响理论。场引起的介电函数变化直接作为四次方谐振分母上的布里渊区积分给出。结果表明，在常见实验条件下，电场调制产生的光谱几乎与未受扰动的介电函数的三阶导数成正比。扰动处理与标准（高场）Franz-Keldysh 理论相关。从物理角度讨论了两种方法之间的差异。开发了抛物线临界点的简化表达式，并用于讨论微扰理论有效性的实验标准。讨论了能带结构分析的应用。特别是，临界点参数（能量、展宽等）几乎独立输入，并且四阶张量线形状的数学形式足够简单，允许根据现有的能带结构计算来计算电反射光谱。
A theory of the electric field effect on the dielectric function of solids is developed by means of a perturbation treatment similar to that used to describe nonlinear optical phenomena. The field-induced change in the dielectric function is given directly as a Brillouin-zone integral over a fourth-power resonant denominator. It is shown that electric field modulation results in spectra nearly proportional to the third derivative of the unperturbed dielectric function for common experimental conditions. The perturbation treatment is related to the standard (high-field) Franz-Keldysh theories. The differences between the two approaches is discussed in physical terms. Simplified expressions for parabolic critical points are developed and used to discuss experimental criteria for the validity of the perturbation theory. Application to band-structure analysis is discussed. In particular, critical-point parameters (energy, broadening, etc.) enter nearly independently, and the mathematical form of the fourth-rank tensorial line shape is simple enough to permit the calculation of electroreflectance spectra from existing band-structure calculations.