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arXiv · 1809.11133

Microwave signatures of $\mathbb{Z}_{2}$ and $\mathbb{Z}_{4}$ fractional Josephson effects

Pedro L. S. Lopes·Samuel Boutin·Philippe Karan·Udson C. Mendes·Ion Garate
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Abstract

We present a many-body exact diagonalization study of the $\mathbb{Z}_2$ and $\mathbb{Z}_4$ Josephson effects in circuit quantum electrodynamics architectures. Numerical simulations are conducted on Kitaev chain Josephson junctions hosting nearest-neighbor Coulomb interactions. The low-energy effective theory of highly transparent Kitaev chain junctions is shown to be identical to that of junctions created at the edge of a quantum spin-Hall insulator. By capacitively coupling the interacting junction to a microwave resonator, we predict signatures of the fractional Josephson effects on the cavity frequency and on time-resolved reflectivity measurements.

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Pedro L. S. Lopes, Samuel Boutin, Philippe Karan, Udson C. Mendes, Ion Garate. 2018-09-28. Microwave signatures of $\mathbb{Z}_{2}$ and $\mathbb{Z}_{4}$ fractional Josephson effects. https://doi.org/10.1103/physrevb.99.045103

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