English

Phase fluctuations in a strongly disordered s-wave superconductor close to the metal-insulator transition

Superconductivity 2011-01-26 v4 Disordered Systems and Neural Networks Strongly Correlated Electrons

Abstract

We explore the role of phase fluctuations in a 3-dimensional s-wave superconductor, NbN, as we approach the critical disorder for the destruction of the superconducting state. Scanning tunneling spectroscopy measurements reveal that in the presence of strong disorder, a finite gap in the electronic spectrum continues to persist at temperatures above Tc. With increase in disorder, the superfluid density is strongly suppressed at low temperatures and evolves towards a linear-T variation at higher temperatures. These observations provide strong evidence that phase fluctuation leads to the formation of a pseudogap state in a disordered conventional superconductor.

Keywords

Cite

@article{arxiv.1006.4143,
  title  = {Phase fluctuations in a strongly disordered s-wave superconductor close to the metal-insulator transition},
  author = {Mintu Mondal and Anand Kamlapure and Madhavi Chand and Garima Saraswat and Sanjeev Kumar and John Jesudasan and L. Benfatto and Vikram Tripathi and Pratap Raychaudhuri},
  journal= {arXiv preprint arXiv:1006.4143},
  year   = {2011}
}

Comments

Minor modifications and figures. (pdf file with figure)