Nonlinearity and Parametric Amplification of Superconducting Nanowire Resonators in Magnetic Field

Parametric amplifiers (PAs) can amplify signals with the minimal amount of noise allowed in quantum mechanics. One restriction is that josephson junctions (JJs) and JJ arrays used to build PAs are incompatible with small (milli-Tesla) magnetic fields. Here we demonstrate the world's first parametric amplifier operating at 2000 times higher magnetic fields (2 Tesla), based on the kinetic inductance of a superconducting nanowire (NbTiN) with no penalty for gain and signal-to-noise ratio. This is important because many applications of PAs related nonlinear devices in quantum optics have high magnetic fields, e.g., spin qubits, Majorana fermions, and nano-magneto-optical systems.