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arXiv · 2004.14261

Topological swing in Bloch oscillations

L. K. Upreti·C. Evain·S. Randoux·P. Suret·A. Amo·P. Delplace
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Abstract

We report new oscillations of wavepackets in quantum walks subjected to electric fields, that decorate the usual Bloch-Zener oscillations of insulators. The number of turning points (or sub-oscillations) within one Bloch period of these oscillations is found to be governed by the winding of the quasienergy spectrum. Thus, this provides a new physical manifestation of a topological property of periodically driven systems that can be probed experimentally. Our model, based on an oriented scattering network, is readily implementable in photonic and cold atomic setups.

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L. K. Upreti, C. Evain, S. Randoux, P. Suret, A. Amo, P. Delplace. 2020-04-29. Topological swing in Bloch oscillations. https://doi.org/10.1103/physrevlett.125.186804

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