Corpus ID: 235265874

Characterization of collective excitations in weakly-coupled disordered superconductors

  title={Characterization of collective excitations in weakly-coupled disordered superconductors},
  author={Bo Fan and Abhisek Samanta and Antonio M. Garc'ia-Garc'ia},
Isolated islands in two-dimensional strongly-disordered and strongly-coupled superconductors become optically active inducing sub-gap collective excitations in the ac conductivity. Here, we investigate the fate of these excitations as a function of the disorder strength in the experimentally relevant case of weak electron-phonon coupling. An explicit calculation of the ac conductivity, that includes vertex corrections to restore gauge symmetry, reveals the existence of collective sub-gap… Expand

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