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arXiv · 1611.07644

Phase-locked array of quantum cascade lasers with an intracavity spatial filter

Lei Wang·Jinchuan Zhang·Zhiwei Jia·Yue Zhao·Chuanwei Liu·Yinghui Liu·Shenqiang Zhai·Zhuo Ning·Fengqi Liu
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Abstract

Phase-locking an array of quantum cascade lasers is an effective way to achieve higher output power and beam shaping. In this article, based on Talbot effect, we show a new-type phase-locked array of mid-infrared quantum cascade lasers with an integrated spatial- filtering Talbot cavity. All the arrays show stable in-phase operation from the threshold current to full power current. The beam divergence of the array device is smaller than that of a single-ridge laser. We use the multi-slit Fraunhofer diffraction mode to interpret the far-field radiation profile and give a solution to get better beam quality. The maximum power is just about 5 times that of a single-ridge laser for eleven-laser array device and 3 times for seven-laser array device. Considering the great modal selection ability, simple fabricating process and the potential for achieving better beam quality and smaller cavity loss, this new-type phase-locked array may be a hopeful and elegant solution to get high power or beam shaping.

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Lei Wang, Jinchuan Zhang, Zhiwei Jia, Yue Zhao, Chuanwei Liu, Yinghui Liu, Shenqiang Zhai, Zhuo Ning, Fengqi Liu. 2016-12-17. Phase-locked array of quantum cascade lasers with an intracavity spatial filter. https://arxiv.org/abs/1611.07644

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