Non-Fermi-Liquid Behavior in Metallic Quasicrystals with Local Magnetic Moments

TL;DR

This paper investigates the non-Fermi-liquid behavior in metallic quasicrystals with magnetic impurities, revealing a power-law distribution of Kondo temperatures that leads to divergent thermodynamic responses at low temperatures.

Contribution

It introduces a model for dilute magnetic impurities in quasicrystals showing a non-universal power-law distribution of Kondo temperatures, explaining non-Fermi-liquid behavior.

Findings

Large fraction of magnetic moments remain unscreened at low T.

Power-law distribution of Kondo temperatures with nonuniversal exponent.

Non-Fermi-liquid behavior with diverging thermodynamic responses.

Abstract

Motivated by the intrinsic non-Fermi-liquid behavior observed in the heavy-fermion quasicrystal $\mbox{Au}_{51}\mbox{Al}_{34}\mbox{Yb}_{15}$, we study the low-temperature behavior of dilute magnetic impurities placed in metallic quasicrystals. We find that a large fraction of the magnetic moments are not quenched down to very low temperatures $T$, leading to a power-law distribution of Kondo temperatures $P(T_{\mbox{K}})\sim T_{\mbox{K}}^{\alpha-1}$, with a nonuniversal exponent $\alpha$, in a remarkable similarity to the Kondo-disorder scenario found in disordered heavy-fermion metals. For $\alpha<1$, the resulting singular $P(T_{\mbox{K}})$ induces non-Fermi-liquid behavior with diverging thermodynamic responses as $T\rightarrow0$.