| We consider effects of magnetic field on the thermoelectric coefficients (TCs) of a single-electron transistor based on a quantum dot strongly coupled to one of the leads by a single-mode quantum point contact (QPC). The reflection in the QPC is presented as the impurity spin flip process in the conventional Kondo effect. The magnetic field induces a transmission asymmetry of spin-up and spin-down channels at the QPC. In the non-perturbation theory, we show the appearance of two new energy scales: T(min )∼EC |r|2 (B/BC)2 depending on the magnetic field B and the field BC corresponding to a full polarization of point contact and T(max )∼EC |r|2 depending on a reflection amplitude r and charging energy EC. The behavior of TCs is discussed in three regimes. The "Giant Fermi liquid" regime in which the TCs behave like those of the Fermi liquid theory at temperatures T≪Tmin. Proximity to "strong non Fermi liquid" regime with thermal coefficients depend logarithmically on temperature can be seen at Tmin<T<Tmax. The perturbative "weak non Fermi liquid" regime holds at Tmax<T<EC. |
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