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arXiv · 2405.10203

Fast Gain Dynamics in Interband Cascade Lasers

Florian Pilat·Andreas Windischhofer·Maximilian Beiser·Vito F. Pecile·Elizaveta Gangrskaia·Audrius Pugžlys·Robert Weih·Johannes Koeth·Andrius Baltuška·Oliver H. Heckl·Benedikt Schwarz
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Abstract

Interband Cascade Lasers (ICL) have matured into a versatile technological platform in the mid-infrared spectral domain. To broaden their applicability even further, ongoing research pursues the emission of ultrashort pulses. The most promising approach is passive mode-locking with a fast saturable absorber. However, despite vast attempts no passive mode-locked ICL has been demonstrated up to date. In this study we perform pump-probe measurements on the ICL gain and show that its dynamics are mainly ($\sim$70%) governed by a fast recovery time of 2 ps. Our findings explain why passive mode-locking has not succeeded so far, shedding a new light on ICL dynamics as we propose strategies to overcome the current limitations.

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Florian Pilat, Andreas Windischhofer, Maximilian Beiser, Vito F. Pecile, Elizaveta Gangrskaia, Audrius Pugžlys, Robert Weih, Johannes Koeth, Andrius Baltuška, Oliver H. Heckl, Benedikt Schwarz. 2024-05-16. Fast Gain Dynamics in Interband Cascade Lasers. https://arxiv.org/abs/2405.10203

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