Development of Superconducting Qubits Based on Nitride Superconductors

Superconducting qubits are one of the promising hardware candidates for quantum computing, and the operation of quantum processors equipped with more than 1000 qubits have been reported. However, to achieve a meaningful quantum computation that has an advantage over classical computation, further improvement in gate fidelity and more precise control of circuit parameters are required, and many challenges remain in realizing such hardware. In this article, we summarize the current status and challenges of superconducting qubits with a focus on the circuit fabrication process and present our research and development of superconducting qubits using nitride superconductors.