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arXiv · 2111.13574

Topologically protected frequency control of broadband signals in dynamically modulated waveguide arrays

Francesco S. Piccioli·Alexander Szameit·Iacopo Carusotto
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Abstract

We theoretically propose a synthetic frequency dimension scheme to control the spectrum of a light beam propagating through an array of evanescently coupled waveguides modulated in time by a propagating sound wave via the acousto-optical effect. Configurations are identified where the emerging two-dimensional synthetic space-frequency lattice displays a non-trivial topological band structure. The corresponding chiral edge states can be exploited to manipulate the frequency spectrum of an incident beam in a robust way. In contrast to previous works, our proposal is not based on discrete high-Q cavity modes, which paves the way to the manipulation of broadband signals.

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Francesco S. Piccioli, Alexander Szameit, Iacopo Carusotto. 2021-11-26. Topologically protected frequency control of broadband signals in dynamically modulated waveguide arrays. https://doi.org/10.1103/physreva.105.053519

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