Highly Sensitive Express Nonlinear Optical Diagnostics of the Crystalline State of Heterostructures Such as Sphalerite

Abstract

The characteristics of a highly sensitive express bench for nonlinear optical diagnosis of crystalline structures such as sphalerite by generation of the second harmonica are presented. The analysis of the possibilities of quantitative and qualitative characterization of the features of the crystalline parameters of the layers of heteroepitaxial structures Cd_xHg_{1 – x}Te on substrates from GaAs with orientation (013) was carried out. The results were obtained by deviations of orientation in layers from the orientation of the substrate, which arose during the epitaxy, to determine the existence of stresses. The high sensitivity of the bench revealed the presence/absence of micro-particles with a disordered crystalline structure. Experimental results of reversible modification of the “in situ” crystalline state of Cd_xHg_{1 – x}Te structures with short-term local radiation exposure of high power laser radiation are given. New experimental data have been presented showing that the components of the nonlineaic susceptibility tensor χ_xyz(ω) of the crystalline structure of Cd_xHg_{1 – x}Te depend on composition and are an order of magnitude larger than similar components of tensor in CdTe and GaAs.