Degree of polarization of luminescence from GaAs and InP as a function of strain: a theoretical investigation

Experimentally, it is known that the degree of polarization (DOP) of luminescence is a sensitive function of strain in III–V materials. It has been assumed that DOP = $-K_e(e_1-e_2)$ and that the rotated degree of polarization = $2K_e{e}_6$ , where $K_e$ is a positive calibration constant, $e_1$ and $e_2$ are the normal components of strain along perpendicular “1” and “2” directions, and $e_6=e_{12}$ is the tensor shear strain. $K_e$ has been measured experimentally for GaAs and InP. In this paper, the results of a simple analytic determination of expressions for DOP as a function of strain are presented. Given the wide ranges reported for the strain deformation potentials $b$ and $d$ , it is not possible to give definitive and meaningful numerical values for expressions for DOP and $K_e$ . However, the sensitivity of DOP to strain suggests that it might be possible to design simple experiments to provide accurate values for the deformation potentials. The $b$ and $d$ deformation potentials might not be independent. For the results presented here and in the limit of isotropic material, an isotropic result for the DOP is found if $d=\sqrt{3}b$ .