Dynamical spin accumulation in large-spin magnetic molecules

TL;DR

This paper investigates how magnetic anisotropy influences frequency-dependent spin transport in large-spin magnetic molecules within the Kondo regime, revealing the dependence on magnetic configuration and intrinsic molecular parameters.

Contribution

It provides a theoretical analysis of dynamical spin accumulation considering magnetic anisotropy effects using the Kubo formalism and NRG, highlighting the role of magnetic configuration and anisotropy types.

Findings

Dynamical spin accumulation occurs at frequencies near the Kondo temperature.

The effect is strongly dependent on the magnetic anisotropy type.

In parallel configuration, accumulation depends on exchange field and Kondo correlations.

Abstract

The frequency-dependent transport through a nano-device containing a large-spin magnetic molecule is studied theoretically in the Kondo regime. Specifically, the effect of magnetic anisotropy on dynamical spin accumulation is of primary interest. Such accumulation arises due to finite off-diagonal in spin components of the dynamical conductance. Here, employing the Kubo formalism and the numerical renormalization group (NRG) method, we demonstrate that the dynamical transport properties strongly depend on magnetic configuration of the device and intrinsic parameters of the molecule. Specifically, the effect of dynamical spin accumulation is found to be greatly affected by the type of magnetic anisotropy exhibited by the molecule, and it develops for frequencies corresponding to the Kondo temperature. For the parallel magnetic configuration of the device, the presence of dynamical spin accumulation is conditioned by the interplay of ferromagnetic-lead-induced exchange field and the Kondo correlations.