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arXiv · 1802.02028

Suppressing spatio-temporal lasing instabilities with wave-chaotic microcavities

Stefan Bittner·Stefano Guazzotti·Yongquan Zeng·Xiaonan Hu·Hasan Yılmaz·Kyungduk Kim·Sang Soon Oh·Qi Jie Wang·Ortwin Hess·Hui Cao
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Abstract

Spatio-temporal instabilities are widespread phenomena resulting from complexity and nonlinearity. In broad-area edge-emitting semiconductor lasers, the nonlinear interactions of multiple spatial modes with the active medium can result in filamentation and spatio-temporal chaos. These instabilities degrade the laser performance and are extremely challenging to control. We demonstrate a powerful approach to suppress spatio-temporal instabilities using wave-chaotic or disordered cavities. The interference of many propagating waves with random phases in such cavities disrupts the formation of self-organized structures like filaments, resulting in stable lasing dynamics. Our method provides a general and robust scheme to prevent the formation and growth of nonlinear instabilities for a large variety of high-power lasers.

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Stefan Bittner, Stefano Guazzotti, Yongquan Zeng, Xiaonan Hu, Hasan Yılmaz, Kyungduk Kim, Sang Soon Oh, Qi Jie Wang, Ortwin Hess, Hui Cao. 2018-09-25. Suppressing spatio-temporal lasing instabilities with wave-chaotic microcavities. https://doi.org/10.1126/science.aas9437

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