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arXiv · 2103.10924

Probing the topology of the two-photon bands via time-dependent quantum walks

Andrei A. Stepanenko·Maxim A. Gorlach
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Abstract

Topological protection of quantum correlations opens new horizons and opportunities in quantum technologies. A variety of topological effects has recently been observed in qubit networks. However, the experimental identification of the topological phase still remains challenging, especially in the entangled many-body case. Here, we propose an approach to independently probe single- and two-photon topological invariants from the time evolution of the two-photon state in a one-dimensional array of qubits. Extending the bulk-boundary correspondence to the two-photon scenario, we show that an appropriate choice of the initial state enables the retrieval of the topological invariant for the different types of the two-photon states in the interacting Su-Schrieffer-Heeger model. Our analysis of the Zak phase reveals additional facets of topological protection in the case of collapse of bound photon pairs.

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Andrei A. Stepanenko, Maxim A. Gorlach. 2021-03-19. Probing the topology of the two-photon bands via time-dependent quantum walks. https://doi.org/10.1364/ol.425841

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