向列相液晶激光器件侧面辐射谱研究

研究了向列相液晶激光器件侧面激光辐射谱，并深入分析了激光辐射机制。分别制备了传统液晶盒和引入SU-8光栅结构的两种器件，并注入向列相液晶TEB30A和激光染料PM597的混合物。利用Nd:YAG固体脉冲激光器倍频出的532 nm激光作为泵浦源正面入射器件，侧面探测激光辐射谱。在传统液晶盒器件侧面，测得575～600 nm范围的随机激光辐射谱。而具有周期100μm和8μm的SU-8光栅结构器件侧面，获得了多波长激光辐射谱。随着泵浦能量增大，最高强度激光辐射峰波长位置出现在583～585 nm和588～592 nm附近，FWHM约0.3 nm。基于光波导理论结合器件结构分析得出，在传统液晶盒中引入SU-8光栅结构增强了液晶器件的光波导效应，是获得多波长激光辐射谱的主要原因。

Emission spectrum of lateral laser in nematic liquid crystal device

The spectra of the lateral laser radiation in nematic liquid crystal (NLC) laser devices are studied, and the characteristics of the laser radiation are deeply analyzed. Two types of NLC cells of standard NLC cell and SU-8 grating based NLC cell are fabricated and injected with a mixture of NLC TEB30A and laser dye PM597, respectively. A frequency-doubled Nd: YAG solid-state pulsed laser with a wavelength of 532 nm is used as the pump source. Random lateral laser radiation in the wavelength of 575-600 nm is observed in the standard NLC cell. Whereas, in the SU-8 grating based NLC cells with periods of 100 μm and 8 μm, the spectrum of the multi-wavelength lateral laser radiation is obtained. With the increase of the pump energy, the strongest lateral laser radiation peaks appear at 583-585 nm and 588-592 nm, and the FWHM is about 0.3 nm. According to the theory of the optical waveguide and analysis of the device structure, the introduction of the SU-8 grating into the standard NLC cell enhances the optical waveguide effect of the LC device and induces multi-wavelength laser radiation.