Performance of a Kinetic Inductance Traveling-Wave Parametric Amplifier at 4 Kelvin: Toward an Alternative to Semiconductor Amplifiers

Most microwave readout architectures in quantum computing or sensing rely on a semiconductor amplifier at 4 K, typically high-electron mobility transistor (HEMT). Despite its remarkable noise performance, conventional HEMT dissipates several milliwatts of power, posing practical challenge to scale up the number qubits sensors addressed these architectures. As an alternative, we present amplification chain consisting kinetic inductance traveling-wave parametric (KITWPA) placed followed by 70 and demonstrate chain-added ${T}_{\mathrm{\ensuremath{\Sigma}}}=6.3\ifmmode\pm\else\textpm\fi{}0.5$ K between 3.5 5.5 GHz. While, principle, any can be limited even practice find performance KITWPA temperature inputs excess ${T}_{\mathrm{ex}}=1.9$ K. The dissipation rf pump constitutes main power load is about 1% that HEMT. These combined values pave way for use as replacement amplifiers.