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arXiv · 1509.03492

Nonlinear parity-time-symmetric transition in finite-size optical couplers

Wiktor Walasik·Chicheng Ma·Natalia M. Litchinitser
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Abstract

Parity-time-symmetric ($\mathcal{PT}$-symmetric) optical waveguide couplers offer a great potential for future applications in integrated optics. Studies of nonlinear $\mathcal{PT}$-symmetric couplers present new possibilities for ultracompact configurable all-optical signal processing. Here, we predict nonlinearly triggered transition from a full to a broken $\mathcal{PT}$-symmetric regime in finite-size systems described by smooth permittivity profiles and, in particular, in a conventional discrete waveguide directional coupler configuration with a rectangular permittivity profile. These results suggest a practical route for experimental realization of such systems.

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Wiktor Walasik, Chicheng Ma, Natalia M. Litchinitser. 2015-09-11. Nonlinear parity-time-symmetric transition in finite-size optical couplers. https://doi.org/10.1364/ol.40.005327

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