TY - JOUR

T1 - Fluctuation theorem in a quantum-dot Aharonov-Bohm interferometer

AU - Utsumi, Yasuhiro

AU - Saito, Keiji

N1 - Copyright:
Copyright 2009 Elsevier B.V., All rights reserved.

PY - 2009/6/8

Y1 - 2009/6/8

N2 - 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 nonequilibrium saddle-point solution for a cumulant-generating function, which satisfies the fluctuation theorem and accounts for the interaction in the mean-field level approximation. The approximation properly leads to the following two consequences. (i) The nonlinear conductance can be an uneven function of the magnetic field for a noncentrosymmetric mesoscopic system. (ii) The nonequilibrium current fluctuations couple with the charge fluctuations via the Coulomb interaction. As a result, nontrivial corrections appear in the nonequilibrium current noise. Nonlinear transport coefficients satisfy universal relations imposed by microscopic reversibility, though the scattering matrix itself is not reversible. When the magnetic field is applied, the skewness in equilibrium can be finite owing to the interaction. The equilibrium skewness is an odd function of the magnetic field and is proportional to the asymmetric component of the nonlinear conductance. The universal relations predicted can be confirmed experimentally.

AB - 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 nonequilibrium saddle-point solution for a cumulant-generating function, which satisfies the fluctuation theorem and accounts for the interaction in the mean-field level approximation. The approximation properly leads to the following two consequences. (i) The nonlinear conductance can be an uneven function of the magnetic field for a noncentrosymmetric mesoscopic system. (ii) The nonequilibrium current fluctuations couple with the charge fluctuations via the Coulomb interaction. As a result, nontrivial corrections appear in the nonequilibrium current noise. Nonlinear transport coefficients satisfy universal relations imposed by microscopic reversibility, though the scattering matrix itself is not reversible. When the magnetic field is applied, the skewness in equilibrium can be finite owing to the interaction. The equilibrium skewness is an odd function of the magnetic field and is proportional to the asymmetric component of the nonlinear conductance. The universal relations predicted can be confirmed experimentally.

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U2 - 10.1103/PhysRevB.79.235311

DO - 10.1103/PhysRevB.79.235311

M3 - Article

AN - SCOPUS:67650070056

VL - 79

JO - Physical Review B-Condensed Matter

JF - Physical Review B-Condensed Matter

SN - 1098-0121

IS - 23

M1 - 235311

ER -