Abstract
We study the low-temperature tunneling density of states of thin wires where superconductivity is destroyed through quantum phase-slip proliferation. Although this regime is believed to behave as an insulator, we show that for a large temperature range this phase is characterized by a conductivity falling off at most linearly with temperature, and has a gapless excitation spectrum. This novel conducting phase results from electron-electron interaction induced pair breaking. Also, it may help clarify the low-temperature metallic features found in films and wires whose bulk realization is superconducting.
- Received 8 August 2011
DOI:https://doi.org/10.1103/PhysRevLett.107.227004
© 2011 American Physical Society