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arXiv · 2603.01672

Extremely weak electron-phonon coupling in Josephson junctions built on InAs on Insulator

Giorgio De Simoni·Sebastiano Battisti·Alessandro Paghi·Lucia Sorba·Francesco Giazotto
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Abstract

InAs-on-Insulator (InAsOI) enables an effective superconducting proximity effect and extremely weak electron-phonon (e-ph) coupling, allowing precise electronic-temperature control with minimal power. Using Josephson junction thermometry, we extract sub-Kelvin e-ph coupling parameters, confirming strong thermal decoupling and robust superconducting performance. The combination of weak e-ph interaction and full electrostatic tunability makes InAsOI a powerful platform for coherent caloritronics, ultrasensitive bolometry, single-photon detection, and gate-controlled superconducting thermal circuits.

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Giorgio De Simoni, Sebastiano Battisti, Alessandro Paghi, Lucia Sorba, Francesco Giazotto. 2026-03-02. Extremely weak electron-phonon coupling in Josephson junctions built on InAs on Insulator. https://arxiv.org/abs/2603.01672

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