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arXiv · 1607.06707

Nonlinear behaviors of parity-time-symmetric lasers

Jianke Yang
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Abstract

We propose a time-dependent partial differential equation model to investigate the dynamical behavior of the parity-time (PT) symmetric laser during the nonlinear stage of its operation. This model incorporates physical effects such as the refractive index distribution, dispersion, material loss, nonlinear gain saturation and self-phase modulation. We show that when the loss is weak, multiple stable steady states and time-periodic states of light exist above the lasing threshold, rendering the laser multi-mode. However, when the loss is strong, only a single stable steady state of broken PT symmetry exists for a wide range of the gain amplitude, rendering the laser single-mode. These results reveal the important role the loss plays in maintaining the single-mode operation of PT lasers.

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Jianke Yang. 2016-07-22. Nonlinear behaviors of parity-time-symmetric lasers. https://doi.org/10.1088/2040-8986%2Faa6901

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