Two-instanton approximation to the Coulomb blockade problem
L.D. Landau Institute for Theoretical Physics, 2 Kosygina Str., Moscow117940, Russia
Laboratory for Condensed Matter Physics, National Research University Higher School of Economics Moscow 101000, Russia
Received July 13, 2016
We develop the two-instanton approximation to the current-voltage characteristic of a single electron transistor within the Ambegaokar–Eckern–Schön model. We determine the temperature and gate voltage dependence of the Coulomb blockade oscillations of the conductance and the effective charge. We find that a small (in comparison with the charging energy) bias voltage leads to significant suppression of the Coulomb blockade oscillations and to appearance of the bias-dependent phase shift.