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Low- and high-frequency noise from coherent two-level systems

Alexander Shnirman·Gerd Schön·Ivar Martin·Yuriy Makhlin
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Abstract

Recent experiments indicate a connection between the low- and high-frequency noise affecting superconducting quantum systems. We explore the possibilities that both noises can be produced by one ensemble of microscopic modes, made up, e.g., by sufficiently coherent two-level systems (TLS). This implies a relation between the noise power in different frequency domains, which depends on the distribution of the parameters of the TLSs. We show that a distribution, natural for tunneling TLSs, with a log-uniform distribution in the tunnel splitting and linear distribution in the bias, accounts for experimental observations.

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Alexander Shnirman, Gerd Schön, Ivar Martin, Yuriy Makhlin. 2005-01-13. Low- and high-frequency noise from coherent two-level systems. https://doi.org/10.1103/physrevlett.94.127002

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