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arXiv · 1901.03636

Transport through a magnetic impurity: a slave-spin approach

Daniele Guerci
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Abstract

We study transport across a magnetic impurity by means of a recently developed slave-spin technique that does not require any constraint. Within a conserving mean-field approximation we find a conductance that displays both the known zero-bias anomaly but also the expected peak at bias of order U. We extend the slave-spin mean-field approximation to study the out of equilibrium transient evolution of a quantum dot. We apply the method to investigate the time-evolution of a quantum dot induced by a time-dependent electrochemical potential applied to the contacts. Similarly to the time-dependent Gutzwiller approximation, the mean-field slave-spin dynamics is able to capture dissipation in the leads, so that a steady-state is reached after a characteristic relaxation time.

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Daniele Guerci. 2019-06-06. Transport through a magnetic impurity: a slave-spin approach. https://doi.org/10.1103/physrevb.99.195409

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