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arXiv · 1510.03065

Broadband parametric amplification with impedance engineering: Beyond the gain-bandwidth product

Tanay Roy·Suman Kundu·Madhavi Chand·A. M. Vadiraj·A. Ranadive·N. Nehra·Meghan P. Patankar·J. Aumentado·A. A. Clerk·R. Vijay
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Abstract

We present an impedance engineered Josephson parametric amplifier capable of providing bandwidth beyond the traditional gain-bandwidth product. We achieve this by introducing a positive linear slope in the imaginary component of the input impedance seen by the Josephson oscillator using a $λ/2$ transformer. Our theoretical model predicts an extremely flat gain profile with a bandwidth enhancement proportional to the square root of amplitude gain. We experimentally demonstrate a nearly flat 20 dB gain over a 640 MHz band, along with a mean 1-dB compression point of -110 dBm and near quantum-limited noise. The results are in good agreement with our theoretical model.

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Tanay Roy, Suman Kundu, Madhavi Chand, A. M. Vadiraj, A. Ranadive, N. Nehra, Meghan P. Patankar, J. Aumentado, A. A. Clerk, R. Vijay. 2016-02-02. Broadband parametric amplification with impedance engineering: Beyond the gain-bandwidth product. https://doi.org/10.1063/1.4939148

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