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arXiv · 2503.09339

Sub-kHz single-frequency pulsed semiconductor laser based on NPRO injection locking

Chunzhao Ma·Wenxun Li·Weitong Fan·Danqing Liu·Xuezhen Gong·Zelong Huang·Jie Xu·Hsien-Chi Yeh·Changlei Guo
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Abstract

We report a single-frequency, narrow-linewidth semiconductor pulsed laser based on pump current modulation and optical injection locking technique. A monolithic non-planar ring oscillator laser is employed as the seed source to guarantee the single-frequency narrow-linewidth performance. Simultaneously, pulse operation is achieved by directly modulating the pump current of the semiconductor laser. The single-frequency pulsed laser (SFPL) has achieved a pulse repetition rate of 50 kHz-1 MHz, a pulse duration ranging from 120 ns to a quasi-continuous state, and a peak power of 160 mW. Moreover, the SFPL has reached a pulsed laser linewidth as narrow as 905 Hz, optical spectrum signal-to-noise ratio of better than 65 dB at a center wavelength of 1064.45 nm. Such extremely narrow-linewidth, repetition-rate and pulse-width tunable SFPL has great potential for applications in coherent LIDAR, metrology, remote sensing, and nonlinear frequency conversion.

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Chunzhao Ma, Wenxun Li, Weitong Fan, Danqing Liu, Xuezhen Gong, Zelong Huang, Jie Xu, Hsien-Chi Yeh, Changlei Guo. 2025-03-12. Sub-kHz single-frequency pulsed semiconductor laser based on NPRO injection locking. https://arxiv.org/abs/2503.09339

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