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arXiv · 1609.05445

$\mathcal{PT}$-symmetric mode-locking

Stefano Longhi
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Abstract

Parity-time ($\mathcal{PT}$) symmetry is one of the most important accomplishments in optics over the past decade. Here the concept of $\mathcal{PT}$ mode-locking of a laser is introduced, in which active phase locking of cavity axial modes is realized by asymmetric mode coupling in a complex time crystal. $\mathcal{PT}$ mode-locking shows a transition from single to double pulse emission as the $\mathcal{PT}$ symmetry breaking point is crossed. The transition can show a turbulent behavior, depending on a dimensionless modulation parameter that plays the same role as the Reynolds number in hydrodynamic flows.

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Stefano Longhi. 2016-09-18. $\mathcal{PT}$-symmetric mode-locking. https://doi.org/10.1364/ol.41.004518

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