Nonequilibrium and Parity Effects in the Tunneling Conductance of Ultrasmall Superconducting Grains
arXiv:cond-mat/9705173 · doi:10.1103/PhysRevB.56.R5759
Abstract
Recent experiment on the tunneling spectra of ultrasmall superconducting grains revealed an unusual structure of the lowest differential conductance peak for grains in the odd charging states. We explain this behavior by nonequilibrium ``gapless'' excitations associated with different energy levels occupied by the unpaired electron. These excitations are generated by inelastic cotunneling.
4 pages, 2 .eps figures included