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arXiv · 1711.02034

Topological Zak Phase in Strongly-Coupled LC Circuits

Tal Goren·Kirill Plekhanov·Félicien Appas·Karyn Le Hur
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Abstract

We show the emergence of topological Bogoliubov bosonic excitations in the relatively strong coupling limit of an LC (inductance-capacitance) one-dimensional quantum circuit. This dimerized chain model reveals a ${\cal Z}_2$ local symmetry as a result of the counter-rotating wave (pairing) terms. The topology is protected by the sub-lattice symmetry, represented by an anti-unitary transformation. We present a methos to measure the winding of the topological Zak phase across the Brillouin zone by a reflection measurement of (microwave) light. Our method probes bulk quantities and can be implemented even in small systems. We study the robustness of edge modes towards disorder.

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Tal Goren, Kirill Plekhanov, Félicien Appas, Karyn Le Hur. 2017-11-06. Topological Zak Phase in Strongly-Coupled LC Circuits. https://doi.org/10.1103/physrevb.97.041106

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