体布拉格光栅外腔实现激光二极管阵列同相模输出

 采用体布拉格光栅作为商用二极管激光阵列外腔，通过将每个单元发出的光反馈回相邻单元实现了外腔锁相。采用这种方法对发光单元宽度为100 μm、周期为200 μm，由49个单元构成的二极管阵列进行了外腔锁相实验，在远场获得了高光束质量、窄带宽的稳定输出。二极管激光阵列自由运转下功率为15 W，经外腔锁相后输出功率为3.67 W，对应光束远场发散角1.47 mrad， 光谱的峰值半宽由1.7 nm压窄到0.17 nm。

In-phase mode selection of high-power diode laser array by VBG external cavity

Phase locking of a high-power DLA in-phase mode output with a volume Bragg grating as an external cavity mirror was achieved experimentally. The linear array consisted of 49 wide-aperture diodes with a diode width of 100 μm and a spacing period of 200 μm was phase locked. Improved output beam quality in the far-field and suppressed bandwidth were demonstrated. The DLA’s single lobe output was 3.67 W for a free running paser of 15 W, the far-field divergence of the phase-locked beam was 1.47 mrad, and the spectral full width at half maximum of the output beam was suppressed from 1.7 nm to 0.17 nm.