Thermoelectric power of Ce(Pd1-xCux)2Si2

S. ENCINA; P. PEDRAZZINI

S.C. de Bariloche

Conferencia; Advanced Topics of Magnetism and Superconductivity (AToMS-2014); 2014

Centro Atomico Bariloche (CNEA) e Instituto Balseiro (CNEA-UNCuyo)

The ground state of the Ce(Pd1-xCux)2Si2 alloy evolves from ordered antiferromagnetism for x ~ 0 to heavy fermion superconductivity for x = 1. We present low temperature thermoelectric power S(T ) of this alloy, showing three characteristic anomalies across the whole composition range: a positive maximum at high temperatures, a negative minimum and a low temperature maximum. We associate the high temperature maximum, also seen in electrical resistivity, to the Kondo e ect and crystal field excitation. We argue that in this alloy the low temperature maximum, displaying a non-monotonous evolution, cannot be simply associated to the Kondo scale and that disorder may be at the origin of the very low S(T ) measured in the 0.2 < x < 0.8 concentration range. A recently acquired dilution refrigerator allowed us to extend electrical resistivity measurements on this system down to 30 mK.