Efficient spectrum analysis for multi-junction superconducting circuit

Abstract The extraction of transition frequencies from a spectrum has conventionally relied on empirical methods, and particularly in complex systems, it is a time-consuming and cumbersome process. To address this challenge, we establish a semi-automated efficient and precise spectrum analysis method. It first employs image processing methods to extract transition frequencies, subsequently estimating the Hamiltonians of a superconducting quantum circuit containing multiple Josephson junctions. In addition, we determine the suitable range of approximations in simulation methods, evaluating the physical reliability of the analysis.