Study of the crossover from ferromagnetic to antiferromagnetic ground state in CeRu2(Ge0.7Si0.3)2 by resistivity measurements under pressure

Abstract

We report a study of the crossover from ferromagnetic (FM) to antiferromagnetic (AFM) ground state in a CeRu2(Ge0.7Si0.3)2 single crystal by resistivity measurements under hydrostatic pressure, p, up to 11.5kbar, using a piston–cylinder clamp. The critical pressure, pc, at which this crossover occurs is only 6kbar (whereas it is close to 25kbar for pure CeRu2Ge2). Unexpectedly, the FM ordering temperature TC does not reach 0K at the FM–AFM transition, but starting from a value of 3.6K at ambient p it is reduced to only 1.68K at 6.1kbar, where the AFM ground state takes place.