Heavy fermion behavior in PrRh2B2C: Excitonic mass enhancement

TL;DR

This study investigates PrRh₂B₂C, a borocarbide compound exhibiting heavy fermion behavior due to excitonic mass enhancement, without magnetic order or superconductivity even under high pressure.

Contribution

It provides the first detailed magnetic and transport analysis of PrRh₂B₂C, revealing its heavy fermion nature linked to crystal field excitations and absence of magnetic or superconducting phases.

Findings

PrRh₂B₂C has a tetragonal structure similar to LuNi₂B₂C.

The compound shows heavy fermion behavior with a high Sommerfeld coefficient.

No magnetic order or superconductivity observed up to 23 kbar pressure.

Abstract

We report magnetic and transport properties of a new quaternary borocarbide PrRh$_{2}$B$_{2}$C, based on magnetisation, resistivity and specific heat studies. This compound forms in LuNi$_{2}$B$_{2}$C-type tetragonal structure (space group {\it I4/mmm}) and does not exhibit magnetic ordering or superconductivity down to 0.5 K. The crystal field analysis of specific heat data suggests a singlet ground state in this compound. The high value of the Sommerfeld coefficient, $\gamma$ $\approx$ 250 mJ/mole K$^{2}$, together with a singlet ground state suggests that the heavy fermion behaviour in PrRh$_{2}$B$_{2}$C results from the interaction of the conduction electrons with the low lying crystal field excitations. No signature of magnetic ordering or superconductivity is observed in PrRh$_{2}$B$_{2}$C under the application of pressure up to 23 kbar.