Electrical resistivity and magnetoresistance of CeRu2Si2 under pressure.

Abstract

The electrical resistivity and high-field magnetoresistance of the heavy-fermion compound ${\mathrm{CeRu}}_{2}$${\mathrm{Si}}_{2}$ have been measured as a function of pressure up to 10 kbar. From the depression of the ${T}^{2}$ resistivity term below \ensuremath{\approxeq}1 K, a rapid increase of the characteristic energy of the quasiparticle system is inferred, which can be represented by a large electronic Gr\"uneisen coefficient \ensuremath{\Omega}\ensuremath{\simeq}185, in excellent agreement with other experimental estimates. It is further observed that the critical field ${H}_{M}$ of the metamagneticlike transition increases at a similar rate, implying that this quantity is governed by the same parameter. The T dependence of \ensuremath{\rho} at fixed field suggests that the transition always occurs for the same value of the effective 4f density of states.