Thermopower of Ce1-xLaxCu4Al in applied magnetic fields

Here we report the continued investigations of thermopower S(T) for Ce1-xLaxCu4Al intermetallic alloys, particularly focusing on the influence of the applied magnetic fields. In comparison to CeCu4Al, the substitution of Ce by La reduces the S(T) values. S(T) of Ce1-xLaxCu4Al compounds exhibit positive values and large maximum at T-max approximate to 30 K. However, the positive sign of S(T) for Ce1-xLaxCu4Al is consistent to that generally observed in Ce-based systems, which is positive due to the location of a narrow Kondo resonance peak slightly above the Fermi energy level (E-F). The large peak may be due to the Kondo effect in the presence of a crystal-field splitting (CEF) of the Ce 4f-electron. The peak position and absolute value above T-max of S(T) is unaffected by an applied magnetic field. At low temperatures the S(T) value depends strongly on the magnetic field. The S/T(T) shows a strong temperature dependence at low temperature which is consistent with the temperature dependence of heat capacity and electrical resistivity. (C) 2013 Elsevier B.V. All rights reserved.