Theoretical modelling of superconducting granular Aluminum nanowire qubits

Conventional Josephson junction-based qubits are promising candidates for practical quantum processors. Although high-quality qubits and high-fidelity gates have been routinely fabricated, qubit coherence time is hindered by several material-based artifacts and losses, such as defects in Josephson junctions due to the fabrication procedure. Recently nanowire qubits have shown a possible candidate for unconventional junctions. They serve as weakly anharmonic inductors without interface defects. T1 and T2 of microsecond order have been observed. We study the problem theoretically and try to theoretically analyze the current-phase relation, anharmonicity, and coherence times in nanowire qubits. This paves the way to study nanowire qubits in circuit-QED setup further.