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Disordered Josephson junction chains: Anderson localization of normal modes and impedance fluctuations

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 Added by Denis Basko
 Publication date 2013
  fields Physics
and research's language is English




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We study the properties of the normal modes of a chain of Josephson junctions in the simultaneous presence of disorder and absorption. We consider the superconducting regime of small phase fluctuations and focus on the case where the effects of disorder and absorption can be treated additively. We analyze the frequency shift and the localization length of the modes. We also calculate the distribution of the frequency-dependent impedance of the chain. The distribution is Gaussian if the localization length is long compared to the absorption length; it has a power law tail in the opposite limit.

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