Interplay of Coulomb interaction and spin-orbit effects in multilevel quantum dots

We study electron transport through amultilevel quantum dot with Rashba spin-orbit interaction in the presence of local Coulomb repulsion. We focus on the parameter regime in which the level spacing is larger than the level broadening. Motivated by recent experiments, we compute the level splitting induced by the spin-orbit interaction at finite Zeeman fields B, which provides a measure of the renormalized spin-orbit energy. This level splitting is responsible for the suppression of the Kondo ridges at finite B characteristic for the multilevel structure. In addition, the dependence of renormalized g factors on the relative orientation of the applied B field and the spin-orbit direction following two different protocols used in experiments is investigated.