Kinetic Inductance Parametric Converter

TL;DR

This paper introduces a kinetic inductance parametric converter using a KI nanowire that achieves high gain and dynamic range for quantum signal processing, with advantages over Josephson-based devices.

Contribution

The paper proposes, demonstrates, and analyzes a KI nanowire-based parametric converter utilizing three-wave mixing for high-gain amplification and squeezing, expanding quantum device capabilities.

Findings

Achieved ~30 dB gain with two-mode amplification and deamplification.

Demonstrated operation at 0.8 GHz resonance separation.

Observed a dynamic range of -108 dBm at 30 dB gain.

Abstract

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.