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arXiv · 2310.01229

High-energy picosecond pulses with a single spatial mode from a passively mode-locked, broad-area semiconductor laser

Mallachi-Elia Meller·Leon Bello·Idan Parshani·Yosef London·Avi Pe'er
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Abstract

We present a mode-locked semiconductor laser oscillator that emits few picosecond pulses (5-8ps at 379MHz repetition) with record peak power (112W) and pulse energy (0.5nJ) directly out of the oscillator (with no amplifier). To achieve this high power performance we employ a high-current broad-area, spatially multi-mode diode amplifier (0.3x5mm), placed in an external cavity that enforces oscillation in a single spatial mode. Consequently, the brightness of the beam is near-ideal ($M^2 = 1.3$). Mode locking is achieved by dividing the large diode chip (edge emitter) into two sections with independent electrical control: one large section for gain and another small section for a saturable absorber. Precise tuning of the reverse voltage on the absorber section allows to tune the saturation level and recovery time of the absorber, which provides a convenient control knob to optimize the mode-locking performance for various cavity conditions.

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Mallachi-Elia Meller, Leon Bello, Idan Parshani, Yosef London, Avi Pe'er. 2023-10-02. High-energy picosecond pulses with a single spatial mode from a passively mode-locked, broad-area semiconductor laser. https://arxiv.org/abs/2310.01229

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