Enhanced light absorption with a cholesteric liquid crystal layer

Abstract

We discuss the trapping features of cholesteric liquid crystal as a self-organized photonic crystal and suggest it for absorption improvement. The imperfection of the absorbing surface is manifested by the reflection originating from the indispensable impedance mismatch. The reflection can be suppressed by an additional surface coating to reflect the light back to the absorber once again. In the simple consideration this reflection loop is possible only twice. For a right-handed CLC coating, the boundary reflection switches the light polarization from left to right circular in the first loop and it switches in the second loop back to the left circular polarization before the emerging light finally escapes from the absorbing process. The enhancement of light absorption is possible in the frequency range as large as the photonic bang gap of the cholesteric layer, which can be adjusted as desired. (C) 2013 Optical Society of America