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arXiv · 2402.11751

A 4-8 GHz Kinetic Inductance Travelling-Wave Parametric Amplifier Using Four-Wave Mixing with Near Quantum-Limit Noise Performance

Farzad Faramarzi·Ryan Stephenson·Sasha Sypkens·Byeong H. Eom·Henry LeDuc·Peter Day
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Abstract

Kinetic inductance traveling-wave parametric amplifiers (KI-TWPA) have a wide instantaneous bandwidth with near quantum-limited performance and a relatively high dynamic range. Because of this, they are suitable readout devices for cryogenic detectors and superconducting qubits and have a variety of applications in quantum sensing. This work discusses the design, fabrication, and performance of a KI-TWPA based on four-wave mixing in a NbTiN microstrip transmission line. This device amplifies a signal band from 4 to 8~GHz without contamination from image tones, which are produced in a separate higher frequency band. The 4 - 8~GHz band is commonly used to read out cryogenic detectors, such as microwave kinetic inductance detectors (MKIDs) and Josephson junction-based qubits. We report a measured maximum gain of over 20 dB using four-wave mixing with a 1-dB gain compression point of -58 dBm at 15 dB of gain over that band. The bandwidth and peak gain are tunable by adjusting the pump-tone frequency and power. Using a Y-factor method, we measure an amplifier-added noise of $ 0.5 \leq N_{added} \leq 1.5$ photons from 4.5 - 8 GHz.

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Farzad Faramarzi, Ryan Stephenson, Sasha Sypkens, Byeong H. Eom, Henry LeDuc, Peter Day. 2024-02-19. A 4-8 GHz Kinetic Inductance Travelling-Wave Parametric Amplifier Using Four-Wave Mixing with Near Quantum-Limit Noise Performance. https://doi.org/10.1063/5.0208110

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