Publications Details

High kinetic inductance NbTiN superconducting transmission line resonators in the very thin film limit

Bretz-Sullivan, Terence M.; Lewis, Rupert; Lima-Sharma, Ana L.; Lidsky, David A.; Smyth, Christopher M.; Harris, Charles T.; Venuti, Michael; Eley, Serena; Lu, Tzu-Ming L.

We examine the DC and radio frequency (RF) response of superconducting transmission line resonators comprised of very thin NbTiN films, < 12 nm in thickness, in the high-temperature limit, where the photon energy is less than the thermal energy. The resonant frequencies of these superconducting resonators show a significant nonlinear response as a function of RF input power, which can approach a frequency shift of Δ f = - 0.15 % in a - 20 dB span in the thinnest film. The strong nonlinear response allows these very thin film resonators to serve as high kinetic inductance parametric amplifiers.