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arXiv · 0712.0221

Tunable resonators for quantum circuits

A. Palacios-Laloy·F. Nguyen·F. Mallet·P. Bertet·D. Vion·D. Esteve
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Abstract

We have designed, fabricated and measured high-Q $λ/2$ coplanar waveguide microwave resonators whose resonance frequency is made tunable with magnetic field by inserting a DC-SQUID array (including 1 or 7 SQUIDs) inside. Their tunability range is 30% of the zero field frequency. Their quality factor reaches up to 3$\times10^4$. We present a model based on thermal fluctuations that accounts for the dependance of the quality factor with magnetic field.

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A. Palacios-Laloy, F. Nguyen, F. Mallet, P. Bertet, D. Vion, D. Esteve. 2007-12-03. Tunable resonators for quantum circuits. https://doi.org/10.1007/s10909-008-9774-x

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