  Parametric converters are parametric amplifiers that mix two spatially
separate nondegenerate modes and are commonly used for amplifying and squeezing
microwave signals in quantum computing and sensing. In Josephson parametric
converters, the strong localized nonlinearity of the Josephson Junction limits
the amplification and squeezing, as well as the dynamic range, in current
devices. In contrast, a weak distributed nonlinearity can provide higher gain
and dynamic range, when implemented as a kinetic inductance (KI) nanowire of a
dirty superconductor, and has additional benefits such as resilience to
magnetic field, higher-temperature operation, and simplified fabrication. Here,
we propose, demonstrate, and analyze the performance of a KI parametric
converter that relies on the weak distributed nonlinearity of a KI nanowire.
The device utilizes three-wave mixing induced by a DC current bias. We
demonstrate its operation as a nondegenerate parametric amplifier with high
phase-sensitive gain, reaching two-mode amplification and deamplification of
$\sim$30 dB for two resonances separated by 0.8 GHz, in excellent agreement
with our theory of the device. We observe a dynamic range of -108~dBm at 30 dB
gain. Our device can significantly broaden applications of quantum-limited
signal processing devices including phase-preserving amplification and two-mode
squeezing.
