Microwave nonlinear effects in He-cooled superconducting microstrip resonators

Sangil Kwon, Anita Fadavi Roudsari, Olaf W. B. Benningshof +8 more

Orest G. Vendik, A. Ya. Zaionchkovskii, S. Kolesov +2 more

A. A. Kalenyuk, S. I. Futimsky, Andrii P. Shapovalov

In this work, we experimentally investigated the nonlinear microwave response of YBa2Cu3O7–x Hilbert fractal superconducting microstrip resonators with sharp and rounded corners. We developed a resonator model that incorporates a distributed current-dependent nonlinear propagation parameter, γ(I), and used the ABCD matrix method for numerical simulations. Our findings demonstrated that the nonlinear response of the resonators can be effectively modeled with a current-proportional propagation parameter, γ∼I. In addition, we observed a significant reduction in the nonlinear response when transitioning from sharp to rounded corners in the resonator design. This work provides valuable insights into improving the design of superconducting resonators by minimizing their nonlinearities, which is crucial for advancing applications in microwave and quantum technologies.

Charles Neill, A. Megrant, M. Lenander +17 more

Antti Jokiluoma

Orest G. Vendik, Irina B. Vendik, T. B. Samoǐlova

The simplest model of nonlinear response of a superconducting thin film is used for modeling the nonlinear phenomena in a superconducting transmission line and a microstrip resonator. The specified characteristic power of the transmission line is suggested to use as a fitting parameter for numerical description of the microstrip line nonlinearity at microwaves. Quantitative agreement of simulated and experimental data has been obtained for the incident power dependent transmission coefficient of a microstrip line section and a high quality microstrip resonator. Numerical results have also been obtained for the power of the third harmonic radiated from the nonlinear resonator.