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arXiv · 0706.3456

Nonperturbative Scaling Theory of Free Magnetic Moment Phases in Disordered Metals

A. Zhuravlev·I. Zharekeshev·E. Gorelov·A. I. Lichtenstein·E. R. Mucciolo·S. Kettemann
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Abstract

The crossover between a free magnetic moment phase and a Kondo phase in low dimensional disordered metals with dilute magnetic impurities is studied. We perform a finite size scaling analysis of the distribution of the Kondo temperature as obtained from a numerical renormalization group calculation of the local magnetic susceptibility and from the solution of the self-consistent Nagaoka-Suhl equation. We find a sizable fraction of free (unscreened) magnetic moments when the exchange coupling falls below a disorder-dependent critical value $J_{\rm c}$. Our numerical results show that between the free moment phase due to Anderson localization and the Kondo screened phase there is a phase where free moments occur due to the appearance of random local pseudogaps at the Fermi energy whose width and power scale with the elastic scattering rate $1/τ$.

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A. Zhuravlev, I. Zharekeshev, E. Gorelov, A. I. Lichtenstein, E. R. Mucciolo, S. Kettemann. 2007-06-23. Nonperturbative Scaling Theory of Free Magnetic Moment Phases in Disordered Metals. https://doi.org/10.1103/physrevlett.99.247202

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