Dual-Wavelength Lasing with Orthogonal Circular Polarizations Generated in a Single Layer of a Polymer-Cholesteric Liquid Crystal Superstructure

Polymers (Basel). 2023 Feb 28;15(5):1226. doi: 10.3390/polym15051226.

Abstract

We investigate the laser emission from a polymer-cholesteric liquid crystal superstructure with coexisting opposite chiralities fabricated by refilling a right-handed polymeric scaffold with a left-handed cholesteric liquid crystalline material. The superstructure exhibits two photonic band gaps corresponding to the right- and left-circularly polarized light. By adding a suitable dye, dual-wavelength lasing with orthogonal circular polarizations is realized in this single-layer structure. The wavelength of the left-circularly polarized laser emission is thermally tunable, while the wavelength of the right-circularly polarized emission is relatively stable. Due to its relative simplicity and tunability characteristics, our design might have broad application prospects in various fields of photonics and display technology.

Keywords: cholesteric liquid crystals; dual-wavelength lasing; filler; orthogonal circular polarizations; polymer composites; polymer–liquid crystal.