Elastic constants of CeCu 6− xAu x at the magnetic instability

Abstract

The elastic constant c 22 of CeCu 6− x Au x with x=0 and x=0.1 has been measured in the temperature range of 0.1 –60 K. The signature of the non-Fermi-liquid behaviour for x = 0.1, right at the onset of antiferromagnetic order, is weak as might be expected from the overall small change of the internal energy U( T) with respect to U( T) of pure CeCu 6. For x = 1 the features in the elastic constant c 33 in field and temperature sweeps are used to confirm the previously obtained complex B- T phase diagram of this anti-ferromagnetically ordered compound.