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arXiv · 2206.00715

A hybrid ferromagnetic transmon qubit: circuit design, feasibility and detection protocols for magnetic fluctuations

Halima Giovanna Ahmad·Valentina Brosco·Alessandro Miano·Luigi Di Palma·Marco Arzeo·Domenico Montemurro·Procolo Lucignano·Giovanni Piero Pepe·Francesco Tafuri·Rosario Fazio·Davide Massarotti
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Abstract

We propose to exploit currently available tunnel ferromagnetic Josephson junctions to realize a hybrid superconducting qubit. We show that the characteristic hysteretic behavior of the ferromagnetic barrier provides an alternative and intrinsically digital tuning of the qubit frequency by means of magnetic field pulses. To illustrate functionalities and limitation of the device, we discuss the coupling to a read-out resonator and the effect of magnetic fluctuations. The possibility to use the qubit as a noise detector and its relevance to investigate the subtle interplay of magnetism and superconductivity is envisaged.

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Halima Giovanna Ahmad, Valentina Brosco, Alessandro Miano, Luigi Di Palma, Marco Arzeo, Domenico Montemurro, Procolo Lucignano, Giovanni Piero Pepe, Francesco Tafuri, Rosario Fazio, Davide Massarotti. 2022-06-01. A hybrid ferromagnetic transmon qubit: circuit design, feasibility and detection protocols for magnetic fluctuations. https://doi.org/10.1103/physrevb.105.214522

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