Magnetism of fine particles of Kondo lattices, obtained by high-energy ball-milling

TL;DR

This study explores how high-energy ball-milling affects the magnetic properties of nano-sized Kondo lattice alloys, revealing significant changes in magnetism and quantum critical behavior in fine particles.

Contribution

It demonstrates that high-energy ball-milling can induce and modify magnetic states in nano-sized Kondo lattice alloys, providing a new method to study strong electron correlations at the nanoscale.

Findings

CeRu2Si2 becomes glassy magnetic below 8 K in fine particles

CeRh2Si2 loses magnetic order down to 0.5 K when milled into nanoparticles

No long-range magnetic order observed at the quantum critical point in the alloy

Abstract

Despite intense research in the field of strongly correlated electron behavior for the past few decades, there has been very little effort to understand this phenomenon in nano particles of the Kondo lattices. In this article, we review the results of our investigation on the fine particles (less than 1 micron) of some of the alloys obtained by high-energy ball-milling to bring out that this synthetic method paves a way to study strong electron correlations in nanocrystals of such alloys. We primarily focus on the alloys of the series, CeRu(2-x)Rh(x)Si2, lying at different positions in Doniach's magnetic phase diagram. While CeRu2Si2, a bulk paramagnet, appears to become magnetic (of a glassy type) below about 8 K in fine particle form, in CeRh2Si2, an antiferromagnet (T_N= 36 K) in bulk form, magnetism is destroyed (at least down to 0.5 K) in fine particles. In the alloy, CeRu(0.8)Rh(1.2)Si2, at the quantum critical point, no long range magnetic ordering is found