Continuous Tensor Network States

Anand Manaparambil (Adam Mickiewicz University Poznań, Poland)

21.05.2021

Non-equilibrium transport through a Quantum dot coupled to Ferromagnetic electrodes
-Anand Manaparambil

Equilibrium studies of how magnetic leads affect the transport through a quantum dot system in the Kondo regime has been well established in the last two decades. Non- equilibrium investigations into such systems were limited by the lack of reliable theoretical framework applicable for accurate calculations of transport in far-from-equilibrium conditions. This gap has been recently filled by a hybrid quench approach combining the Numerical Renormalization Group (NRG) and time-dependent Density Matrix Renormalization Group (tDMRG) methods in the Matrix Product State framework. We employ the NRG-tDMRG quench approach to investigate the non-equilibrium spin-resolved transport through a quantum dot coupled to ferromagnetic leads, focusing on the Kondo regime. In particular, we study the dependence of the zero-bias peak exhibited by the non- equilibrium conductance, a characteristic feature of the Kondo effect, on various system parameters such as lead spin polarization, dot energy level, external magnetic field and temperature.Anand is a PhD student of Prof. Irek Weymann, who was postdoc in Munich 10 years ago. Anand's work is a follow-up project of the PhD thesis research conducted by our former group member Frauke Schwarz, on nonequilibrium transport for the single-impurity Anderson model, computed using a hybrid NRG/DMRG method. The new twist is to consider ferromagnetic leads, modeled using spin-dependent tunneling rates.