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arXiv · 1804.04573

Unidirectional light transport in dynamically modulated waveguides

Momchil Minkov·Shanhui Fan
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Abstract

One-way edge states at the surface of photonic topological insulators are of significant interest for communications, nonlinear and quantum optics. Moreover, when reciprocity is broken in a photonic topological insulator, these states provide protection against disorder, which is of particular importance for slow light applications. Achieving such a one-way edge state, however, requires the construction of a two-dimensional structure. Here, we show how unidiriectional Floquet bands can arise in purely one-dimensional, adiabatically-modulated dynamic systems, in contrasts with the higher dimensionality needed in topological insulators. We also show that, using realistic experimental parameters, the concept can be implemented using both a coupled-resonator optical waveguide and a photonic crystal waveguide. Furthermore, we illustrate the associated protection against disorder, and find it to be of a novel nature when compared to Floquet topological insulators.

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Momchil Minkov, Shanhui Fan. 2018-04-12. Unidirectional light transport in dynamically modulated waveguides. https://doi.org/10.1103/physrevapplied.10.044028

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