Nonequilibrium transport in superconducting tunneling structures
Abstract
We derive the current-voltage (I-V) characteristics of far from equilibrium superconducting tunneling arrays and find that the energy relaxation ensuring the charge transfer occurs in two stages: (i) the energy exchange between charge carriers and the intermediate bosonic agent, environment, and (ii) relaxing the energy further to the (phonon) thermostat, the bath, provided the rate of the environmental modes-phonon interactions is slower than their energy exchange rate with the tunneling junction. For a single junction we find I∝(V/R)ln(Λ/V), where R is the bare tunnel resistance of the junction and Λ is the high energy cut-off of the electron-environment interaction. In large tunneling arrays comprised of macroscopic number of junctions, low-temperature transport is governed by the cotunneling processes losing energy to the electron-hole environment. Below some critical temperature, T∗, the Coulomb interactions open a finite gap in the environment excitations spectrum blocking simultaneously Cooper pair and normal excitations currents through the array; this is the microscopic mechanism of the insulator-to-superinsulator transition.
- Publication:
-
Physica C Superconductivity
- Pub Date:
- December 2010
- DOI:
- 10.1016/j.physc.2009.11.008
- Bibcode:
- 2010PhyC..470S.935C