功率稳定且波长可调谐的窄线宽分布式反馈半导体激光器

Widely Tunable Distributed Feedback Semiconductor Lasers with Constant Power and Narrow Linewidth

提出一种新型的分布式反馈(DFB)半导体激光器,该激光器具有宽带波长可调谐、线宽窄、功率稳定的特点。该DFB激光器芯片通过采用非对称相移光栅结构,有效地压窄了输出光信号的线宽。基于高精度的温度和电流控制,有效控制激光器内部载流子动态特性与材料折射率,使得激光器输出波长可以实现宽带调谐,并且输出光功率保持稳定。其中,电流控制精度为10μA,温度控制精度为0.004℃,激光器的波长调谐范围为3.5nm,输出光功率为7.4mW,边模抑制比为52.7dB,线宽约为220kHz。该激光器有望应用于可调谐二极管激光吸收光谱(TDLAS)的研究中。

A widely tunable distributed feedback （DFB） semiconductor laser with constant power and narrow linewidth is fabricated. The laser chip is based on the asymmetric phase-shifted DFB structure, which can effectively narrow the bandwidth of the output. By precisely controlling the temperature and driving current, the dynamic characteristic of internal carriers and the refractive index of the material can be controlled effectively, so wide-band tuning wavelength and constant output power are obtained. The wavelength tuning range is over 3.5 nm, the laser power is 7.4 mW, the linewidth is about 220 kHz and the side mode suppression radio is 52.7 dB. This laser has wide application prospects for tunable diode laser absorption spectroscopy （TDLAS）.