  Samples of heavy fermion compound CeCu6 were prepared by hot-press technique.
Temperature-dependent (5-300 K) thermoelectric transport properties of the
samples were measured. The dimensionless figure-of-merit (ZT) was optimized by
varying the hot-pressing temperature. Our measurements of thermal conductivity
show that the lowest hot pressing temperature (450 C) produces the lowest
thermal conductivity. Electrical resistivity increases significantly while the
Seebeck coefficient decreases with decrease in the hot pressing temperature. As
the hot-pressing temperature decreases, electronic contribution to the total
thermal conductivity decreased more rapidly than the lattice contribution did.
As a result, for lower hot-pressing temperature the gain in thermal
conductivity reduction was offset by the loss in power factor. Our ZT
calculations show a broad peak with a maximum value of 0.024 at 60 K for the
sample hot pressed at 800 C. The pronounced low-temperature ZT peak emphasizes
the importance of this heavy fermion system as a potential p-type
thermoelectric for solid state cooling applications.
