Time-domain simulation of the circular Bragg phenomenon exhibited by axially excited chiral sculptured thin films

Abstract

We present simulations of the transmission and reflection of narrow-extent pulses incident upon a chiral sculptured thin film (STF) along its axis of spirality, when the circular Bragg phenomenon is excited. Even though the frequency-domain reflection and transmission spectrums of a sufficiently thick chiral STF slab acquire final shapes within the Bragg regime, the shape and the duration of the transmitted pulse change with slab thickness over the entire range of our simulations. The emergence of a multiple-hump structure in the transmitted pulse is relevant to the use of chiral STFs in digital optics communication.