We theoretically investigate the intrinsic optical anisotropy or polarization induced by the microscopic interface asymmetry (MIA) in no-common-atom (NCA) InAs/GaSb superlattices (SLs) grown along the [001] direction. The eight-band $\mathbf{K}\cdot \mathbf{P}$ model is used to calculate the electronic band structures and incorporates the MIA effect. A Boltzmann equation approach is employed to calculate the optical properties. We found that in NCA InAs/GaSb SLs, the MIA effect causes a large in-plane optical anisotropy for linearly polarized light and the largest anisotropy occurs for light polarized along the [110] and $\left[1\overline{1}0\right]$ directions. The relative difference between the optical-absorption coefficient for [110]-polarized light and that for $\left[1\overline{1}0\right]$-polarized light is found to be larger than 50%. The dependence of the in-plane optical anisotropy on temperature, photoexcited carrier density, and layer width is examined in detail. This study is important for optical devices which require the polarization control and selectivity.

• Received 5 October 2010

DOI:https://doi.org/10.1103/PhysRevB.82.235422