Theory of gyrotropy of semiconducting quantum wells (scientific summary)

A theory of optical phenomena caused by the gyrotropy of semiconducting quantum wells has been developed. It has been demonstrated that the study of the reflection of light near a light exciton makes it possible to detect the natural optical activity of quantum wells. The reflection coefficients in a magnetic field lying in the plane of the quantum well carry information on magnetic gyrotropy described by contributions to the optical response that are bilinear in the wave vector of light and the field strength and are caused simultaneously by the gyrotropy of the system and the magnetic field. It has been shown that magnetogyrotropic effects are resonantly enhanced near a heavy exciton. The estimates of gyrotropic and magnetogyrotropic contributions to reflection are consistent with existing experimental data.