Converse effect of pressure on quadrupolar and magnetic transition in Ce$_{3}$Pd$_{20}$Si$_{6}$

TL;DR

This study investigates how pressure influences the phase transitions in Ce$_{3}$Pd$_{20}$Si$_{6}$, revealing a merging of transitions at 6.2 kbar and confirming the robustness of quantum criticality under pressure.

Contribution

It demonstrates the effect of pressure on the phase transitions in Ce$_{3}$Pd$_{20}$Si$_{6}$ and extends the global phase diagram for heavy fermion quantum criticality.

Findings

Transitions merge at 6.2 kbar under pressure.

Quantum criticality remains robust with pressure.

Pressure has a converse effect on the two phase transitions.

Abstract

The heavy fermion compound Ce$_{3}$Pd$_{20}$Si$_{6}$ displays unconventional quantum criticality as the lower of two consecutive phase transitions is fully suppressed by magnetic field. Here we report on the effects of pressure as additional tuning parameter. Specific heat and electrical resistivity measurements reveal a converse effect of pressure on the two transitions, leading to the merging of both transitions at 6.2 kbar. The field-induced quantum criticality is robust under pressure tuning. We rationalize our findings within an extended version of the global phase diagram for antiferromagnetic heavy fermion quantum criticality.