Regular Self-Pulsations in External Cavity Mid-IR Quantum Cascade Lasers

Nikola N. Vukovic; Jelena V. Radovanovic; Vitomir B. Milanovic; Alexander V. Antonov; Dmitry I. Kuritsyn; Vladimir V. Vaks; Dmitri L. Boiko

arXiv · 1902.00205

Regular Self-Pulsations in External Cavity Mid-IR Quantum Cascade Lasers

Nikola N. Vukovic·Jelena V. Radovanovic·Vitomir B. Milanovic·Alexander V. Antonov·Dmitry I. Kuritsyn·Vladimir V. Vaks·Dmitri L. Boiko

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Abstract

We show theoretically and experimentally that a quantum cascade laser (QCL) in an external Fabry-Perot cavity (EC) can produce regular self-pulsations (SP) of the output intensity at frequencies ~75 GHz. We recognize that the propagation delay in EC provides QCL with a "memory" mechanism to preserve the regularity and coherence of the pulse train on the intervals significantly exceeding the sub-picosecond gain coherence and gain recovery times. These results may point to novel practical approaches for producing regular time-domain SPs and pulse trains in the Mid-IR QCLs. Otherwise, due to a multimode Risken-Nummedal-Graham-Haken (RNGH) instability, free-running FP QCLs exhibit SPs at Rabi flopping frequencies in the THz range, which in addition, reveal a quasi-periodic chaotic behavior if the cavity round trip time is a few picoseconds or more.

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Nikola N. Vukovic, Jelena V. Radovanovic, Vitomir B. Milanovic, Alexander V. Antonov, Dmitry I. Kuritsyn, Vladimir V. Vaks, Dmitri L. Boiko. 2019-02-01. Regular Self-Pulsations in External Cavity Mid-IR Quantum Cascade Lasers. https://arxiv.org/abs/1902.00205

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