Circular dichroism and absorption in a finite cholesteric liquid crystal layer with an isotropic defect layer inside

Abstract

ABSTRACTCircular dichroism and absorption are calculated for one-dimensional chiral soft substance (a cholesteric liquid crystal, CLC) cells with an isotropic defect layer. The photonic density of states (PDS), circular dichroism, absorption and emission dependencies are calculated as functions of the parameters characterising absorption and gain. The absorption and gain effects in chiral photonic systems with a defect layer are established and it is shown that in some cases the subject system can work as: a low threshold laser, a multi-position trigger, a total wide/narrow band absorber, a wide/narrow band filter/mirror, etc. This work demonstrates the effects of absorption and emission in photonic crystal (PC) layers, and offers a novel approach to understanding of tunable soft photonic substances.