Thermoelectric power of delafossite-type metallic oxide PdCoO2

Thermoelectric power of metallic cobalt oxide PdCoO2, of which Co valence is 3+ in the low spin state and the density of state at the Fermi level is dominated by Pd 4d electrons, has been clarified between 100 and 400 K. It is found that the temperature dependence of thermoelectric power shows a gradual change. The values of thermoelectric power in the measured temperature range are 2–4 μV/K. These values comparable to normal conventional metals may be attributable to the Fermi level just at the bottom of the deep cave of the density of state.