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arXiv · 1404.1792

Tunable microwave impedance matching to a high impedance source using a Josephson metamaterial

Carles Altimiras·Olivier Parlavecchio·Philippe Joyez·Denis Vion·Patrice Roche·Daniel Esteve·Fabien Portier
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Abstract

We report the efficient coupling of a $50\,\Omega$ microwave circuit to a high impedance conductor. We use an impedance transformer consisting of a $\lambda/4$ co-planar resonator whose inner conductor contains an array of superconducting quantum interference devices (SQUIDs), providing the resonator with a large and tunable lineic inductance $\mathcal{L}\sim 80 \mu_0$, resulting in a large characteristic impedance $Z_C\sim 1\,\mathrm{k}\Omega$. The impedance matching efficiency is characterized by measuring the shot noise power emitted by a dc biased high resistance tunnel junction connected to the resonator. We demonstrate matching to impedances in the $15$ to $35\,\mathrm{k}\Omega$ range with bandwidths above $100\,\mathrm{MHz}$ around a resonant frequency tunable in the $4$ to $6\,\mathrm{GHz}$ range.

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Carles Altimiras, Olivier Parlavecchio, Philippe Joyez, Denis Vion, Patrice Roche, Daniel Esteve, Fabien Portier. 2014-04-07. Tunable microwave impedance matching to a high impedance source using a Josephson metamaterial. https://doi.org/10.1063/1.4832074

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