Nonequilibrium Kondo effect in a Quantum Dot coupled to Ferromagnetic leads*

The accurate quantitative description of the nonequilibrium transport in interacting nanoscale junctions presents a formidable challenge. Tensor network methods have entered the arena as a highly competitive, versatile, and well-controlled approach. In particular, we use a recently developed hybrid numerical renormalization group-density matrix renormalization group thermofield quench approach based on a matrix product state framework. With this, we obtain quantitatively reliable predictions for spintronic transport through a Kondo-correlated quantum dot coupled to ferromagnetic leads in far-from-equilibrium conditions. We primarily study the bias dependence of the differential conductance through the system, which shows a finite zero-bias peak and a characteristic Kondo energy scale in the applied bias. We show that this Kondo scale decreases with an increase in the spin polarization on the leads and an exchange field can develop across the system. As a key result, we demonstrate that an additional external magnetic field can be utilized to achieve a full Kondo revival in an out-of-equilibrium setting.