In situ non-destructive measurement of Josephson junction resistance using fritting contact technique

Conventional four-probe methods for measuring the resistance of Josephson junctions can damage superconducting thin films, making them unsuitable for frequency measurements of superconducting qubits. In this study, we present a custom probe station measurement system that employs the fritting contact technique to achieve in situ, non-destructive measurements of Josephson junction resistance. Our experimental results demonstrate that this method allows for accurate prediction of qubit frequency with an error margin of 17.2 MHz. Moreover, the fritting contact technique does not significantly affect qubit coherence time or the integrity of the superconducting film, confirming its non-destructive nature. This innovative approach provides a dependable foundation for frequency tuning and addressing frequency collision issues, thus supporting the advancement and practical deployment of superconducting quantum computing.