Generalized ellipsometry determination of non-reciprocity in chiral silicon sculptured thin films



We report on angle-resolved reflection-type generalized ellipsometry investigations of form-birefringent chiral silicon sculptured thin films. The nanodimensional structures within the sculptured thin films are designed in geometries of left-handed hollow-core three-, four-, and five-fold, and solid-core continuous screws. We identify their structurally induced non-reciprocal optical properties by comparison between off-diagonal Mueller matrix elements upon reversal of the light direction. The observed non-reciprocity cannot be described by the piecewise homogeneous approximation scheme using chiral arrangements of dielectrically anisotropic layers. We show that a simple sequence of light interaction with an ideal isotropic chiral rotator and an arbitrarily anisotropic but non-chiral surface produces non-reciprocity. We provide estimates of the optical rotary power of the nanostructures. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)