A1 Journal article (refereed)
Phase-dependent microwave response of a graphene Josephson junction (2022)

Haller, R., Fülöp, G., Indolese, D., Ridderbos, J., Kraft, R., Cheung, L. Y., Ungerer, J. H., Watanabe, K., Taniguchi, T., Beckmann, D., Danneau, R., Virtanen, P., & Schönenberger, C. (2022). Phase-dependent microwave response of a graphene Josephson junction. Physical Review Research, 4(1), Article 013198. https://doi.org/10.1103/PhysRevResearch.4.013198

JYU authors or editors

Virtanen, Pauli

Publication details

All authors or editors: Haller, R.; Fülöp, G.; Indolese, D.; Ridderbos, J.; Kraft, R.; Cheung, L. Y.; Ungerer, J. H.; Watanabe, K.; Taniguchi, T.; Beckmann, D.; et al.

Journal or series: Physical Review Research

eISSN: 2643-1564

Publication year: 2022

Publication date: 14/03/2022

Volume: 4

Issue number: 1

Article number: 013198

Publisher: American Physical Society (APS)

Publication country: United States

Publication language: English

DOI: https://doi.org/10.1103/PhysRevResearch.4.013198

Publication open access: Openly available

Publication channel open access: Open Access channel

Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/81929

Web address of parallel published publication (pre-print): https://arxiv.org/abs/2108.00989

Abstract

Gate-tunable Josephson junctions embedded in a microwave environment provide a promising platform to in situ engineer and optimize novel superconducting quantum circuits. The key quantity for the circuit design is the phase-dependent complex admittance of the junction, which can be probed by sensing a radio frequency SQUID with a tank circuit. Here, we investigate a graphene-based Josephson junction as a prototype gate-tunable element enclosed in a SQUID loop that is inductively coupled to a superconducting resonator operating at 3 GHz. With a concise circuit model that describes the dispersive and dissipative response of the coupled system, we extract the phase-dependent junction admittance corrected for self-screening of the SQUID loop. We decompose the admittance into the current-phase relation and the phase-dependent loss, and as these quantities are dictated by the spectrum and population dynamics of the supercurrent-carrying Andreev bound states, we gain insight to the underlying microscopic transport mechanisms in the junction. We theoretically reproduce the experimental results by considering a short, diffusive junction model that takes into account the interaction between the Andreev spectrum and the electromagnetic environment, from which we estimate lifetimes on the order of ∼10 ps for nonequilibrium populations.

Keywords: nanoelectronics; electronic circuits; superconductors; superconductivity; graphene; microwaves