The Kondo effect and weak localization

TL;DR

This paper reviews the Kondo effect, emphasizing how non-magnetic scattering influences the resistivity in thin alloys, challenging previous assumptions that only host metal and impurity determine the Kondo temperature.

Contribution

The paper presents theoretical analysis showing non-magnetic scattering suppresses Kondo resistivity in thin alloy samples, highlighting size and disorder effects.

Findings

Non-magnetic scattering reduces Kondo resistivity in thin alloys

Kondo temperature is affected by sample size and disorder

Theoretical work aligns with experimental observations

Abstract

The word Kondo means battle in Swahili. This coincidence is fortuitous because in the Kondo effect, a battle inevitably ensues anytime a magnetic impurity is placed in a non-magnetic metal. Below some energy scale, the Kondo temperature ($T_k$), a lone magnetic impurity is robbed of its spin. Above the Kondo temperature, rapid spin-flip scattering produces a temperature-dependent correction to the resistivity of the form, $B_k\ln T$. Until recently, both the Kondo resistivity and $T_k$ were thought to be determined solely by the host metal and the magnetic impurity. However, numerous presentations in this volume attest, there is now overwhelming evidence that both are affected by the size of the sample as well as non-magnetic random scattering. In this paper, I will focus on the theoretical work we have performed on the experiments revealing that non-magnetic scattering suppppresses the Kondo resistivity in thin Kondo alloys.