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arXiv · 2204.05087

Electromotive force in driven topological quantum circuits

Ahmed Kenawy·Fabian Hassler·Roman-Pascal Riwar
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Abstract

Time-dependent control of superconducting quantum circuits is a prerequisite for building scalable quantum hardware. The quantum description of these circuits is complicated due to the electromotive force (emf) induced by time-varying magnetic fields. Here, we examine how the emf modifies the fractional Josephson effect. We show that a time-varying flux introduces a new term that depends on the geometry of both the circuit and the applied magnetic field. This term can be probed via current and charge measurements in closed-loop and open-circuit geometries. Our results refine the current understanding of how to properly describe time-dependent control of topological quantum circuits.

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Ahmed Kenawy, Fabian Hassler, Roman-Pascal Riwar. 2022-04-11. Electromotive force in driven topological quantum circuits. https://doi.org/10.1103/physrevb.106.035430

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