Specific Heat of CeRhSb Doped with Pd

Abstract

CeRhSb is known as a Kondo insulator with a hybridization gap Eg/kB  7 K. By doping CeRhSn with Pd this gap is strongly reduced and completely removes for x>0.08 in the system of CeRh1-xPdxSb alloys. The specific heat C of the samples 0x0.08 shows the heavy-Fermi-like behavior in the form of an strongly enhanced Sommerfeld coefficient CTT, which follows below 8 K a power law over a decade in temperature. Our measurements suggest that the enhanced  value originates from correlated, residual in-gap states at the Fermi level.