2025/11/21 by J. Basset, Basset, Julien, Ognjen Stanisavljević +7
Computer Science · Physics and Astronomy · #FOS: Physical sciences #Mechanical and Optical Resonators #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Quantum Information and Cryptography #Topological Materials and Phenomena
paper · doi:10.48550/arxiv.2511.17470
openalex publication_date 2025/11/21 · openalex created_date 2025/11/25 · openalex updated_date 2026/07/28
We demonstrate a single-photon detector operating in the microwave domain, based on photo-assisted quasiparticle tunneling events that poison a superconducting island. The detection relies on continuously monitoring the island's charge parity using microwave reflectometry. This scheme achieves 10% detection efficiency with sub \SI50\ns time resolution and short dead time (∼ \SI1\us), for microwave photons at \SI10\GHz. The detector features three junctions connected to a superconducting island, which together carry out photoelectric conversion and charge readout. The enhanced light--matter coupling, crucial to photon to quasiparticle conversion, is provided by a granular aluminum-based high-impedance microwave resonator. The time resolved detection of itinerant microwave photon opens up new perspectives in quantum sensing, microwave quantum optics and mesoscopic physics.