Influence of bias voltage noise on the Inelastic Cooper-Pair Tunneling Amplifier (ICTA)

TL;DR

This paper demonstrates that the Inelastic Cooper-Pair Tunneling Amplifier (ICTA) can achieve near-quantum-limited noise performance comparable to Josephson parametric amplifiers, with specific gain and noise characteristics influenced by bias voltage noise.

Contribution

The study experimentally and theoretically shows how bias voltage noise impacts ICTA's noise performance, highlighting conditions for near-quantum-limited amplification.

Findings

Achieved 20 dB gain with noise below 1.7 times the quantum limit.

ICTA's noise performance depends on the integral voltage bias noise relative to the bandwidth.

Bias voltage noise below a certain threshold enables near-quantum-limited amplification.

Abstract

We experimentally show that the Inelastic Cooper-Pair Tunneling Amplifier (ICTA), implementing a DC-powered parametric amplification scheme, can achieve gain and noise performance similar to that of Josephson parametric amplifiers. Using experimental data and simulations, we show that the ICTA has near-quantum-limited noise as long as the integral voltage bias noise divided by the superconducting flux quantum is below the amplification bandwidth. We observe a gain of 20 dB with noise below 1.7 times the quantum limit when the full width at half maximum of the integral voltage noise, expressed as frequency, is 5.6 MHz.