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Microscopic Model of Critical Current Noise in Josephson Junctions

Magdalena Constantin·Clare C. Yu
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Abstract

We present a simple microscopic model to show how fluctuating two--level systems in the Josephson junction tunnel barrier of thickness $L$ can modify the potential energy of the barrier and produce critical current noise spectra. We find low frequency $1/f$ noise that goes as $L^5$. Our values are in good agreement with recent experimental measurements of critical current noise in Al/AlO$_{x}$/Al Josephson junctions. We also investigate the sensitivity of the noise on the nonuniformity of the tunnel barrier.

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Magdalena Constantin, Clare C. Yu. 2007-11-13. Microscopic Model of Critical Current Noise in Josephson Junctions. https://doi.org/10.1103/physrevlett.99.207001

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