Gigantic reflectance anisotropy of the [110] face of cubic ZnSe in the excitonic part of the spectrum

Optical response nonlocality in cubic ZnSe in the proximity of an excitonic absorption resonance leads to a gigantic optical anisotropy (deltan/n appr oximate to 0.1). The anisotropy cause a polarization azimuth rotation, in s cale of several degrees, for the light reflected from the [110] crystal fac et. The anisotropy is described by quadratic. in respect to the light wave vector terms in the dielectric tensor of the crystal. It results from the: spin-orbit interaction induced, electron-wave vector linear terms in the ex citon dispersion, bound to non-centrosymmetricity of the crystalline struct ure.