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arXiv · 2210.05966

Spatial spin-spin correlations of the single-impurity Anderson model with a ferromagnetic bath

Peng Fan·Ning-Hua Tong·Zhen-Gang Zhu
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Abstract

We investigate the interplay between the Kondo effect and the ferromagnetism by an one dimension Anderson impurity model with a spin partially polarized bath, using the projective truncation approximation under Lacroix basis.The equal-time spatial spin-spin correlation function (SSCF) is calculated. For the case of spin-unpolarized conduction electrons, it agrees qualitatively with the results from density matrix renormalization group (DMRG). For system with partially spin-polarized conduction electrons, an oscillation in the envelope of SSCF emerges due to the beating of two Friedel oscillations associated to two spin-split Fermi surfaces of conduction electrons. The period is proportional to the inverse of magnetic field $h$. A fitting formula is proposed to perfectly fits the numerical results of SSCF in both the short- and long-range regions. For large enough bath spin polarization, a bump appears in the curve of the integrated SSCF. It marks the boundary between the suppressed Kondo cloud and the polarized bath sites.

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Peng Fan, Ning-Hua Tong, Zhen-Gang Zhu. 2022-10-12. Spatial spin-spin correlations of the single-impurity Anderson model with a ferromagnetic bath. https://doi.org/10.1103/physrevb.106.155130

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