Nonequilibrium magnetotransport through a quantum dot: An interpolative perturbative approach

We study the differential conductance, spectral density, and magnetization for a quantum dot coupled to two conducting leads as a function of bias voltage V-ds, magnetic field B, and temperature T. The system is modeled with the Anderson model solved using a spin-dependent interpolative perturbative approximation in the Coulomb repulsion U that conserves the current. For large enough magnetic field, the differential conductance as a function of bias voltage shows split peaks. This splitting is larger than the corresponding splitting in the spectral density of states rho(d)(omega), in agreement with experiment.