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تسجيل مستخدم جديدPerturbative theory of the non-equilibrium singlet-triplet transition
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We study equilibrium and non-equilibrium properties of a two-level quantum dot close to the singlet-triplet transition. We treat the on-site Coulomb interaction and Hunds rule coupling perturbatively within the Keldysh formalism. We compute the spectral functions and the differential conductance of the dot. For moderate interactions our perturbative approach captures the Kondo effect and many of the experimentally observed properties.
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