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arXiv:2310.05238 · IEEE Transactions on Applied Superconductivity

Design and Simulation of a Transmon Qubit Chip for Axion Detection

Roberto Moretti, Hervè Atsè Corti, Danilo Labranca, F. Ahrens, Guerino Avallone, D. Babusci, Leonardo Banchi, C. Barone, M. Beretta, M. Borghesi, B. Buonomo, Enrico Calore, Giovanni Carapella, F. Chiarello, Alessandro Cian, Alessandro Cidronali, Filippo Costa, Alessandro Cuccoli, Alessandro D’Elia, Daniele Di Gioacchino, Stefano Di Pascoli, P. Falferi, Marco Fanciulli, M. Faverzani, Giulietto Felici, E. Ferri, Giovanni Filatrella, L. Foggetta, Claudio D. Gatti, Andrea Giachero, Francesco Giazotto, D. Giubertoni, V. Granata, Claudio Guarcello, G. Lamanna, Carlo Ligi, Giovanni Maccarrone, Massimo Macucci, Giuliano Manara, Federica Mantegazzini, Paolo Marconcini, B. Margesin, F. Mattioli, Andrea Miola, Angelo Nucciotti, Luca Origo, S. Pagano, Federico Paolucci, L. Piersanti, A. Rettaroli, S. Sanguinetti, Sebastiano Fabio Schifano, P. Spagnolo, S. Tocci, A. Toncelli, G. Torrioli, Andrea Vinante

Published Jan 19, 2024• 8 citations
arXivHTMLPDF

Abstract

Quantum Sensing is a rapidly expanding research field that finds one of its applications in Fundamental Physics, as the search for Dark Matter. Devices based on superconducting qubits have already been successfully applied in detecting few-GHz single photons via Quantum Non-Demolition measurement (QND). This technique allows us to perform repeatable measurements, bringing remarkable sensitivity improvements and dark count rate suppression in experiments based on high-precision microwave photon detection, such as for Axions and Dark Photons search. In this context, the INFN Qub-IT project goal is to realize an itinerant single-photon counter based on superconducting qubits that will exploit QND for enhancing Axion search experiments. In this study, we present Qub-IT's status towards the realization of its first superconducting qubit device, illustrating design and simulation procedures and the characterization of fabricated Coplanar Waveguide Resonators (CPWs) for readout. We match target qubit parameters and assess a few-percent level agreement between lumped and distributed element simulation models. We reach a maximum internal quality factor of 9.2×105for -92 dBm on-chip readout power.

DOI
10.1109/tasc.2024.3350582

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