New regime of the Coulomb blockade in quantum dots

We consider how the absence of thermalization affects the classical Coulomb blockade regime in quantum dots. By solving the quantum kinetic equation in the experimentally accessible regime when the dot has two relevant occupation states, we calculate the current–voltage characteristics for arbitrary coupling to the leads. If the couplings are strongly asymmetric, the Coulomb staircase is practically reduced to the first step, which is independent of the charging energy, when the Fermi energy is comparatively small, while the standard thermalized results are recovered in the opposite case. When the couplings are of the same order, the absence of thermalization has a new, striking signature—a robust additional peak in the differential conductance.