外腔锁相宽发光区二极管激光列阵研究

利用简单的外腔，实现了具有宽发光区的商用半导体二极管激光列阵(DLA)的外腔锁相。光谱测量表明，DLA的谱宽由自由运行时的1.9 nm压缩到了0.16 nm，峰值波长由803.8 nm调整到805.5 nm；实测远场光瓣间角距等于1.6 mrad，即波长与发光单元间距之比，表明列阵运行在基超模(或最高阶超模)；峰谷结构调制度大于0.8。观察表明，外腔长度在1/10~1/6泰伯距离内变化时，锁相均能实现。实验事实表明锁相是交叉注入锁定的结果。利用半导体激光注入锁定理论，定性分析了外腔DLA由自由振荡向锁相过渡的过程，预言了锁相场波长应出现在自由运行DLA光谱长波端，实验也证实了这一事实。

Phase locked broad-stripe diode laser array in an external cavity

By using an external cavity, a commercially available broad-stripe semiconductor diode laser array(DLA) has been phase locked. Measurements show that the spectral width of the phase-locked DLA is reduced to 0.16 nm compared to 1.9 nm of the free-running DLA, and the peak wavelength is shifted from 803.8 nm to 805.5 nm. An angular spacing between the lobes of the far field pattern of 1.6 mrad, coincident with the ratio of the wavelength to emitter distance, indicates that the DLA is operated in the fundamental(or highest) super mode. The modulation depth of the peak-valley pattern is measured to be larger than 0.8. It has also been verified that phase locking can be achieved for external cavity length between 1/10 to 1/16 of the Talbot distance zT. Based on experimental facts, it is believe