Research for large thermoelectric responses of transition metal oxides by controlling nanostructure

2015 Fiscal Year Final Research Report

• Project/Area Number: 25400378
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Condensed matter physics II
• Research Institution: Kagoshima University
• Principal Investigator: Okuda Tetsuji 鹿児島大学, 理工学域工学系, 准教授 (20347082)
• Co-Investigator(Kenkyū-buntansha): SAITOH Tomohiko 東京理科大学, 理学部, 教授 (30311129) ; KAJIMOTO Ryoichi 独立行政法人日本原子力研究開発機構, その他部局等, 主任研究員 (30391254)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 熱電材料 / 遷移金属酸化物

Outline of Final Research Achievements

In this research, we have investigated a mechanism of enhancement of thermoelectric property in the electron-doped SrTiO3 by a substitution of Mn ions. By measurements of macroscopic properties such as thermoelectric property, Hall coefficient, magnetic property, and specific heat, and that of phonon excitations by an inelastic neutron scattering measurement, we have shown the possibility that the enhancement is caused by a nontrivial enhancement of low-energy phonon excitation and an enhancement of Seebeck coefficient due to some interaction between itinerant electrons and localized spins of Mn ions.
Furthermore, we have investigated a magnetic excitation of antiferromagnetic triangular lattice CuCrO2 which is one of candidates of p-type thermoelectric oxides by an inelastic neutron scattering measurement and have clarified electronic structures of hole-doped CuCrO2 and the related materials by photoemission spectroscopy.

Free Research Field

物性物理学