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arXiv · 2005.07636

Nonlinear transition between PT-symmetric and PT-broken modes in coupled fiber lasers

Sergey V. Suchkov·Dmitry V. Churkin·Andrey A. Sukhorukov
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Abstract

We present a systematic analysis of the stationary regimes of nonlinear parity-time(PT) symmetric laser composed of two coupled fiber cavities. We find that power-dependent nonlinear phase shifters broaden regions of existence of both PT-symmetric and PT-broken modes, and can facilitate transitions between modes of different types. We show the existence of non-stationary regimes and demonstrate an ambiguity of the transition process for some of the unstable states. We also identify the presence of higher-order stationary modes, which return to the initial state periodically after a certain number of round-trips.

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Sergey V. Suchkov, Dmitry V. Churkin, Andrey A. Sukhorukov. 2020-05-15. Nonlinear transition between PT-symmetric and PT-broken modes in coupled fiber lasers. https://doi.org/10.1364/oe.397853

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