Effect of capacitive coupling in superconducting coplanar waveguide resonator

Abstract

Superconducting coplanar waveguide (SCPW) resonators with high quality (Q) factor are widely used for developing quantum sensors and quantum information processors. Here we conducted numerical simulations of SCPW resonators to investigate the relationship between the Q factor and the coupling capacitance of the resonator. Varying the geometrical shape of both ends and coupling parameters of the SCPW resonator resulted in a change of the coupling capacitances and the Q factor as well. Our calculation results indicate that the performance of the SCPW resonator is highly sensitive to the capacitive coupling and searching for an optimal coupling condition would be crucial for developing high-performance SCPW resonator.