Microwave Transmission in Superconducting TiN CPW Resonator with High and Nonlinear Kinetic Inductance

Abstract

We report the transmission characteristics in microwave regime of a superconducting coplanar waveguide (CPW) resonator fabricated with a high kinetic inductance titanium nitride (TiN, Tc~4.27 K and R.R.R.~1.1178) thin film deposited by DC magnetron sputtering. A comparative study with a Nb resonator demonstrates that a kinetic inductance comparable to or higher than the magnetic inductance, which is geometrically determined, leads to a remarkable redshift in the resonant frequency in spite of the identical geometry. The kinetic inductance contributes effectively to an increase in the relative permeability of the resonator system. In high power or nonlinear regimes, anomalous responses, due to the so-called Kerr nonlinearity, with highly asymmetric and even discontinuous behaviors in transmission are observed. High kinetic inductance superconducting films are expected to be used to constitute nonlinear circuit elements such as Josephson junctions as well as geometrically-compact linear elements incorporated into a superconducting quantum processing device.