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Coherent instabilities in a semiconductor laser with fast gain recovery

C. Y. Wang·L. Diehl·A. Gordon·C. Jirauschek·F. X. Kaertner·A. Belyanin·D. Bour·S. Corzine·G. Hoefler·M. Troccoli·J. Faist·F. Capasso
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Abstract

We report the observation of a coherent multimode instability in quantum cascade lasers (QCLs), which is driven by the same fundamental mechanism of Rabi oscillations as the elusive Risken-Nummedal-Graham-Haken (RNGH) instability predicted 40 years ago for ring lasers. The threshold of the observed instability is significantly lower than in the original RNGH instability, which we attribute to saturable-absorption nonlinearity in the laser. Coherent effects, which cannot be reproduced by standard laser rate equations, can play therefore a key role in the multimode dynamics of QCLs, and in lasers with fast gain recovery in general.

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C. Y. Wang, L. Diehl, A. Gordon, C. Jirauschek, F. X. Kaertner, A. Belyanin, D. Bour, S. Corzine, G. Hoefler, M. Troccoli, J. Faist, F. Capasso. 2006-12-08. Coherent instabilities in a semiconductor laser with fast gain recovery. https://doi.org/10.1103/physreva.75.031802

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