Dyakonov–Tamm waves guided by the planar surface of a chiral sculptured thin film

Abstract

Propagation of Dyakonov–Tamm waves guided by the interface of air and a chiral sculptured thin film (STF) was investigated theoretically. The solution of the dispersion equation showed that the direction of propagation is either unrestricted or almost unrestricted in the interface plane. For very limited ranges of the direction of propagation, multiple Dyakonov–Tamm waves may even exist. These surface waves were theoretically found to be excitable in the Otto prism-coupled configuration by an incident plane wave of either linear polarization state, thereby lending hope for an easy way to observe Dyakonov–Tamm waves experimentally.