Plasmonic Modes in hybrid Josephson Junction Arrays

Alex Kirchner; Simon Feyrer; Vjeko Dimić; Johanna Berger; Davide Curcio; Giorgio Biasiol; Michael Prager; Matthias Kronseder; Dominique Bougeard; Nicola Paradiso; Christoph Strunk; Leandro Tosi

arXiv · 2609.31069

Plasmonic Modes in hybrid Josephson Junction Arrays

Alex Kirchner·Simon Feyrer·Vjeko Dimić·Johanna Berger·Davide Curcio·Giorgio Biasiol·Michael Prager·Matthias Kronseder·Dominique Bougeard·Nicola Paradiso·Christoph Strunk·Leandro Tosi

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Abstract

We present microwave characterization measurements of Josephson junction arrays (JJAs) based on epitaxial Al-InAs quantum well heterostructure. The Josephson inductance of the constituent planar junctions can be derived by probing the low-energy plasmon modes of these devices. Applying an out-of-plane magnetic field gives rise to a Fraunhofer-like diffraction pattern, from which the current-phase relation and the effective transparency can be extracted. JJAs can be used to achieve high inductances, suitable for the implementation of quantum circuits. They also provide an excellent test-bed for studying the microscopic excitations of hybrid superconductor-semiconductor devices associated with the presence of Andreev states. Here, we demonstrate their tunability over a broad range of out-of-plane magnetic fields.

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Alex Kirchner, Simon Feyrer, Vjeko Dimić, Johanna Berger, Davide Curcio, Giorgio Biasiol, Michael Prager, Matthias Kronseder, Dominique Bougeard, Nicola Paradiso, Christoph Strunk, Leandro Tosi. 2026-09-25. Plasmonic Modes in hybrid Josephson Junction Arrays. https://arxiv.org/abs/2609.31069

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