We have developed and measured a high-gain quantum-limited microwave parametric amplifier based on a superconducting lumped LC resonator with the inductor L including an array of 8 superconducting quantum interference devices (SQUIDs). This amplifier is parametrically pumped by modulating the flux threading the SQUIDs at twice the resonator frequency. Around 5 GHz, a maximum gain of 31 dB, a product amplitude-gain x bandwidth above 60 MHz, and a 1 dB compression point of -123 dBm at 20 dB gain are obtained in the non-degenerate mode of operation. Phase sensitive amplification-deamplification is also measured in the degenerate mode and yields a maximum gain of 37 dB. The compression point obtained is 18 dB above what would be obtained with a single SQUID of the same inductance, due to the smaller nonlinearity of the SQUID array.
@article{arxiv.1409.5630,
title = {High-gain weakly nonlinear flux-modulated Josephson parametric amplifier using a SQUID-array},
author = {X. Zhou and V. Schmitt and P. Bertet and D. Vion and W. Wustmann and V. Shumeiko and D. Esteve},
journal= {arXiv preprint arXiv:1409.5630},
year = {2015}
}