Suppression of dense Kondo state in CeB6 under pressure

TL;DR

This study investigates how high pressure affects the dense Kondo state in CeB6, revealing suppression of Kondo behavior and a transition to a conventional metal without structural change up to 85 GPa.

Contribution

It provides experimental evidence that high pressure suppresses the dense Kondo state in CeB6 without inducing a structural phase transition.

Findings

Kondo state suppressed at 43 GPa

Resistivity maximum disappears between 12 and 20 GPa

CeB6 remains structurally stable up to 85 GPa

Abstract

To investigate whether the dense Kondo compound CeB6 might evolve into a topological insulator under sufficient pressure, four-point electrical resistivity measurements have been carried out over the temperature range 1.3 K to 295 K in a diamond anvil cell to 122 GPa. The temperature of the resistivity maximum initially increases slowly with pressure but disappears between 12 and 20 GPa. The marked changes observed under pressure suggest that a valence and/or structural transition may have occurred. Synchrotron x-ray diffraction measurements, however, fail to detect any change in crystal structure to 85 GPa. Although a transition into an insulating phase is not observed, this dense Kondo system is completely suppressed at 43 GPa, leaving behind what appears to be a conventional Fermi liquid metal.