795 nm亚波长光栅耦合腔垂直腔面发射激光器的超窄线宽特性

Ultra-narrow linewidth characteristics of 795-nm subwavelength grating-coupled cavity vertical cavity surface emitting laser

基于共振耦合腔理论,提出并设计了基于亚波长光栅耦合腔的795 nm垂直腔面发射激光器(vertical cavity surface emitting laser,VCSEL),利用COMSOL软件有限元方法对多光腔耦合线宽压窄机制和影响因素进行了详细分析,研究发现,当光子在多耦合腔中进行谐振时,通过合理设计光栅耦合腔参数,精确调控激光器多耦合腔相位匹配,极大地促进了光谱线宽共振压窄效应,并最终获得了高光束质量795 nm VCSEL 激光器的超窄线宽输出.理论结果表明,当耦合腔间隔层厚度为180 nm时,反射光谱冷腔线宽Δλ_(c)可以达到7 pm,为实现VCSEL激光器kHz量级光谱线宽输出奠定了理论基础.

In this paper,the 795-nm vertical cavity surface emitting laser(VCSEL) with sub-wavelength grating coupled cavity is proposed and designed based on the theory of resonant coupled cavity,and the mechanism of multi-cavity coupling linewidth narrowing and influencing factors are analyzed in detail by using the COMSOL software finite element method.The analysis results show that when photonic resonance takes place in a multicoupled cavity,the grating-coupled cavity with reasonable design parameters and the multi-coupled cavity formed by precisely controlled lasers are phase-matched,which greatly strengthens the narrowing effect of the spectral linewidth resonance,and a 795-nm VCSEL laser with high beam quality and ultra-narrow linewidth output is obtained,finally.Theoretical results display that the reflection spectrum cold cavity linewidth Δλ_(c) of the coupling cavity with a thickness of 180 nm of the spacer layer can reach 7 pm,which lays a theoretical foundation for achieving a kHz-level spectral linewidth output of VCSEL lasers.