In-Plane Optical Anisotropy of [001]-Oriented Asymmetrical Quantum Wells

We consider polarization-sensitive optical effects in quantum wells grown from zinc blend semiconductor materials on the basis of an envelope-function approximation. Particular attention is paid to the case of normal incidence of linearly polarized light on a quantum well grown in the [001] crystallographic direction. We demonstrate that for the [001]-oriented quantum wells characterized by structure inversion asymmetry, in-plane optical anisotropy can be governed by a bulk-related microscopic mechanism. This intrinsic mechanism is due to the Gamma(8) valence band interaction, which is linear in the hole momentum operator and is allowed for bulk cubic crystals lacking a space inversion center. Analytical results are obtained in the limiting case of a strong confinement regime. The resulting in-plane optical anisotropy and related effects can be detected in the vicinity of exciton resonances.