Fluctuation Theorem in a Quantum-Dot Aharonov-Bohm Interferometer

In the present study, we investigate the full counting statistics in a two-terminal Aharonov-Bohm interferometer embedded with an interacting quantum dot. We introduce a novel saddle-point solution for a cumulant-generating function, which satisfies the fluctuation theorem and accounts for the interaction in the mean-field level approximation. Nonlinear transport coefficients satisfy universal relations imposed by microscopic reversibility, though the scattering matrix itself is not reversible. The skewness can be finite even in equilibrium, owing to the interaction and is proportional to the asymmetric component of nonlinear conductance.