Charge-Doping driven Evolution of Magnetism and non-Fermi-Liquid Behavior in the Filled Skutterudite CePt4Ge12-xSbx

TL;DR

This study investigates how charge doping via Sb substitution in CePt4Ge12 influences its magnetic properties and non-Fermi-liquid behavior, revealing a transition from intermediate-valence to antiferromagnetic order driven by Kondo physics.

Contribution

It demonstrates the evolution of magnetism and non-Fermi-liquid behavior in CePt4Ge12-xSbx due to charge doping, supported by experimental and band-structure calculations.

Findings

Emergence of antiferromagnetic order with increased Sb content

Observation of an extended non-Fermi-liquid region

Support for a Kondo-disorder model explaining the behavior

Abstract

The filled-skutterudite compound CePt4Ge12 is situated close to the border between intermediate-valence of Ce and heavy-fermion behavior. Substitution of Ge by Sb drives the system into a strongly correlated and ultimately upon further increasing the Sb concentration into an antiferromagnetically ordered state. Our experiments evidence a delicate interplay of emerging Kondo physics and the formation of a local 4f moment. An extended non-Fermi-liquid region, which can be understood in the framework of a Kondo-disorder model, is observed. Band-structure calculations support the conclusion that the physical properties are governed by the interplay of electron supply via Sb substitution and the concomitant volume effects.