TY - JOUR
T1 - Contribution of electronic structure to the large thermoelectric power in layered cobalt oxides
AU - Takeuchi, Tsunehiro
AU - Kondo, Takeshi
AU - Takami, Tsuyoshi
AU - Takahashi, Hirofumi
AU - Ikuta, Hiroshi
AU - Mizutani, Uichiro
AU - Soda, Kazuo
AU - Funahashi, Ryoji
AU - Shikano, Masahiro
AU - Mikami, Masashi
AU - Tsuda, Syunsuke
AU - Yokoya, Takayoshi
AU - Shin, Shik
AU - Muro, Takayuki
PY - 2004/3/19
Y1 - 2004/3/19
N2 - With a strong help of high-resolution photoemission spectroscopy we demonstrate in this paper that the large thermoelectric power observed in the layered cobalt oxides, such as Ca3Co4O9, Na0.6CoO2, and Bi2Sr2Co2O9, can be well accounted for with the Boltzmann-type metallic electrical conduction. An intense peak with 1.5-2 eV in width was observed in the photoemission spectra with its center at 1.0 eV below the Fermi level EF in these compounds. The density of states at EF is finite but negligibly small at room temperature, because EF is located near the high-energy edge of this narrow band. We calculated thermoelectric power S using the Boltzmann transport equation with the electronic structure near EF determined by the photoemission measurement. The calculated S shows fairly good consistency with the measured value both in its magnitude and the temperature dependence.
AB - With a strong help of high-resolution photoemission spectroscopy we demonstrate in this paper that the large thermoelectric power observed in the layered cobalt oxides, such as Ca3Co4O9, Na0.6CoO2, and Bi2Sr2Co2O9, can be well accounted for with the Boltzmann-type metallic electrical conduction. An intense peak with 1.5-2 eV in width was observed in the photoemission spectra with its center at 1.0 eV below the Fermi level EF in these compounds. The density of states at EF is finite but negligibly small at room temperature, because EF is located near the high-energy edge of this narrow band. We calculated thermoelectric power S using the Boltzmann transport equation with the electronic structure near EF determined by the photoemission measurement. The calculated S shows fairly good consistency with the measured value both in its magnitude and the temperature dependence.
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U2 - 10.1103/PhysRevB.69.125410
DO - 10.1103/PhysRevB.69.125410
M3 - Article
AN - SCOPUS:2342424579
SN - 1098-0121
VL - 69
JO - Physical Review B-Condensed Matter
JF - Physical Review B-Condensed Matter
IS - 12
ER -