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arXiv · 1409.5630

High-gain weakly nonlinear flux-modulated Josephson parametric amplifier using a SQUID-array

X. Zhou·V. Schmitt·P. Bertet·D. Vion·W. Wustmann·V. Shumeiko·D. Esteve
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Abstract

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.

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X. Zhou, V. Schmitt, P. Bertet, D. Vion, W. Wustmann, V. Shumeiko, D. Esteve. 2014-09-19. High-gain weakly nonlinear flux-modulated Josephson parametric amplifier using a SQUID-array. https://doi.org/10.1103/physrevb.89.214517

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