Asymmetric charge susceptibility in a mesoscopic interferometer

We investigate the nonequilibrium charge response of a mesoscopic interferometer (an Aharonov‐Bohm ring) with an interacting quantum dot inserted in one of its arms. The differential conductance is asymmetric when the applied magnetic field reverses its direction. We relate the origin of this effect to the asymmetric charge susceptibility of the dot, which yields, in the mean‐field approximation of the Anderson Hamiltonian, the nonequilibrium potential of the dot. We find that the charge susceptibility becomes an odd function of the flux for symmetric tunnel couplings and examine its behavior when the temperature is lowered below the Kondo temperature.