APL Quantum

Aharonov–Casher effect and the coherent flux tunneling in the hybrid charge quantum interference device

Jacob Dunstan, Rais S. Shaikhaidarov, Artem Shesterikov, Ilya Antonov, Kyung Ho Kim, S. Linzen, Evgeni V. Il’ichev, V.N. Antonov, O. V. Astafiev

Published Apr 9, 2026• 0 citations

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Abstract

By exploiting the Aharonov–Casher effect, we demonstrate a significant suppression of magnetic flux tunneling in a hybrid charge quantum interference device. The main part of this device is two Josephson junctions with a small superconducting island between them. To minimize phase fluctuations across Josephson junctions, this structure is embedded in a compact superinductive NbN loop. The interference between the flux tunneling paths is determined by the island-induced charge, which is controlled by an external voltage. The charge sensitive operation of the device is subjected to poisoning by the quasiparticles generated in the NbN film.

DOI: 10.1063/5.0314400

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