Exploiting the Kerr-free point of a SNAIL for improvement of dynamic range in parametric amplifiers*

Quantum-limited Josephson parametric amplifiers are an important component for most superconducting qubit readout methods. While being well optimized for the noise performance, the scalability of resonant parametric amplifiers is determined predominantly by the ability to boost their dynamic range and bandwidth. The dynamic range of the state-of-the-art "paramps" is limited by the spurious Kerr-induced Stark shifts which detune the paramp from its operating point, leading to the reduction of gain with increased signal power. We show that using a Superconducting Nonlinear Asymmetric Inductive eLement (SNAIL) as an active element, we are able to tune to a Kerr-free sweet spot in the presence of the pump, which exhibits significantly improved 1 dB compression power.