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arXiv · 1610.06004

Robust unidirectional transport in a one-dimensional metacrystal with long-range hopping

Stefano Longhi
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Abstract

In two- and three-dimensional structures, topologically-protected chiral edge modes offer a powerful mean to realize robust light transport. However, little attention has been paid so far to robust one-way transport in one-dimensional systems. Here it is shown that unidirectional transport, which is immune to disorder and backscattering, can occur in certain one-dimensional metacrystals with long-range hopping without resorting to topological protection. Such metacrystals are described by an effective Hermitian Hamiltonian with broken time reversal symmetry, and transport does not require adiabatic (Thouless) pumping. A simple implementation in optics of such one-dimensional metacrystals, based on transverse light dynamics in a self-imaging optical cavity with phase gratings, is suggested

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Stefano Longhi. 2016-10-19. Robust unidirectional transport in a one-dimensional metacrystal with long-range hopping. https://doi.org/10.1209/0295-5075/116/30005

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