Analysis of laser radiation performance of fingerprint-texture cholesteric liquid crystal device

Low-cost tunable lasers have broad application prospects in optoelectronics. In this paper, a laser device based on fingerprint-textured cholesteric liquid crystal (CLC) was designed and fabricated, in which a narrow linewidth single-mode laser output on the side of the device was realized. The planar helical structure of the "fingerprint-texture"of CLC was obtained by the combined effect of externally applied electric field and substrate surface anchoring. Under the pumping light of a Nd:YAG solid-state pulsed second harmonic laser with the wavelength of 532 nm, the lasing emission wavelength of our CLC device changes non-monotonically with gradually increasing electric field, which first shifting from 568.5 nm to 609.2 nm and then shifting from 609.2 nm to 586.2 nm. And the observed spectral tuning of the lasing emission was reproducible and reversible. The analysis shows that the output laser radiation was the result of the Bragg reflection feedback provided by the fingerprint-texture.