Semiconductor laser bar and semiconductor outer cavity

Abstract

The invention discloses a semiconductor laser bar and a semiconductor outer cavity, and belongs to the field of semiconductor laser array coherent beam combining. The semiconductor laser bar comprises a plurality of light-emitting units and non-light-emitting areas located between the adjacent light-emitting units; the light-emitting units are in one-to-one correspondence with wave crests of high-order Hermitian beams, the non-light-emitting areas are in one-to-one correspondence with pitch lines of the high-order Hermitian Gaussian beams, the width of each light-emitting unit is equal to the width between zero points at the two ends of the corresponding wave crest, each non-light-emitting area coincides with the corresponding pitch line; the width of each light emitting unit is unequal; the high-order Hermitian Gaussian beam is generated by interaction of the semiconductor laser bar and the external cavity. The non-uniformly distributed semiconductor laser bar supports high-order Hermitian Gaussian mode oscillation, when a high-order Hermitian Gaussian mode is generated in a cavity, the introduced coupling loss is lowest, the width of each light emitting unit is matched with the high-order Hermitian Gaussian mode, the coupling efficiency can be improved, and the power and stability of coherent beam combination are further improved.

Description

technical field [0001] The invention belongs to the field of coherent beam combining of semiconductor laser arrays, and more specifically relates to a semiconductor laser bar and a semiconductor external cavity. Background technique [0002] Semiconductor laser has always been the frontier hotspot of laser research. The biggest problem limiting the wide application of high-power semiconductor lasers is their poor beam quality. At present, the spectral beam combining technology is mainly used to improve the brightness of high-power semiconductor lasers. This method greatly improves the brightness of the semiconductor laser array. However, in the process of advancing the semiconductor laser to a higher power, it is limited by the semiconductor gain bandwidth and cannot achieve a larger number of semiconductor laser beams. In addition, spectral beam combining technology usually requires a relatively complex coating technology as the basis, which is difficult to realize. [0...

AI Technical Summary

Problems solved by technology

However, the beam combining cavity based on Talbot imaging technology has very serious limitations on the power and brightness of semiconductor lasers: the coupling efficiency of Talbot imaging is weak, resulting in limited phase locking ability of the Talbot field. When the operating current is high, the gain is large, and a single There is spontaneous radiation amplification inside the light-emitting unit, which will lead to parasitic oscillations inside the light-emitting unit, and incoherent parasitic oscillations will suppress coherent oscillations, thereby reducing the beam combining efficiency; random phase and intensity fluctuations of semiconductor lasers will destroy the light field cycle structure, leading to the deterioration of the self-reproducing Talbot image, and the deterioration of the Talbot image will lead to further deterioration of the periodic field, and finally lead to a serious decline in coherent beam combining

Using the Talbot image to achieve coherent beam combining requires precise control of the phase fluctuation amplitude of each light-emitting unit in the laser array, which requires high precision and relatively low efficiency, making it difficult to achieve

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