Principle of tunable chemical vapor detection exploiting the angular Goos–Hänchen shift in a magneto-electric liquid-crystal-based system

Abstract

We present a theoretical investigation of the angular Goos–Hänchen shift (GHS) of a Gaussian light beam upon reflection from a multilayered structure consisting of a nematic liquid crystal (LC) cell sandwiched between electrodes and deposited on a magneto-electric/non-magnetic bilayer. We show that the angular GHS can be enhanced and controlled both via a voltage applied to the LC cell and a magnetization reversal in the magneto-electric film. We describe the principle of an optical sensor of chemical vapors in the vicinity of the structure based on the voltage-induced tunability of the angular GHS.