Interference and Coulomb correlation effects in spin-polarized transport through coupled quantum dots

Spin-dependent transport through two coupled single-level quantum dots attached to ferromagnetic leads with collinear (parallel and antiparallel) magnetizations is analyzed theoretically. The intra-dot Coulomb correlation is taken into account, whereas the inter-dot Coulomb repulsion is neglected. Transport characteristics, including conductance and tunnel magnetoresistance associated with the magnetization rotation from parallel to antiparallel configurations, are calculated by the noneqiulibrium Green function technique. The relevant Green functions are derived by the equation of motion method in the Hartree-Fock approximation. We have found a splitting of the Fano peak, induced by the intra-dot Coulomb interaction. Apart from this, the intra-dot electron correlations are shown to lead to an enhancement of the tunnel magnetoresistance effect.