表面液晶-垂直腔面发射激光器温度特性的研究

本文利用向列相液晶层作为激光偏振调控单元，涂覆于垂直腔面发射激光器（VCSEL）表面，测量并分析了不同温度下VCSEL正交线偏振光的阈值电流、峰值光功率和I-P特性. 实验结果表明：温度为293 K时，涂覆液晶后激光偏振第一跳变点和第二跳变点之间的电流值ΔI增大了2.2 mA，比无液晶时增大1倍. 温度为313 K、注入电流为3 mA时，两种正交线偏振光的光功率差ΔP由133.6 μW增大到248.8 μW，进一步增加了线偏振光的各向异性. 表面液晶层的引入有效地扩大了VCSEL的正交线偏振态稳定范围和光功率差，为实现液晶VCSEL高温单偏振稳定的设计和器件制备提供了理论和实验基础.关键词：垂直腔面发射激光器向列相液晶偏振态

Temperature characteristics of VCSEL with liquid crystal overlay

The 850-nm vertical-cavity surface-emitting laser (VCSEL) with liquid crystal overlay is presented utilizing the birefringence of nematic liquid crystal. Threshold current, peak of optical power and I-P characteristics at different temperatures were studied. At 293 K, the current between the first polarization hop and the second one has an increase of 2.2 mA after overlaying the liquid crystal. At 313 K and 3 mA, the optical power difference between the two orthogonally polarized lights increases from 133.6 to 248.8 μW. The experimental results show that the nematic liquid crystal enlarges the stable range and the discrete of optical power of orthogonally polarized state. Our research could provide insight into the design and fabrication of VCSEL with stable polarization at high temperatures.
Keywords：VCSELnematic liquid crystalpolarization