[16p-Z19-1~23] 10.1 Emerging materials in spintronics and magnetics (including fabrication and characterization methodologies)

▲ [16p-Z19-2] Seebeck-driven Colossal Transverse Thermoelectric Generation

〇Weinan Zhou¹, Kaoru Yamamoto¹, Asuka Miura¹, Ryo Iguchi¹, Yoshio Miura^1,2, Ken-ichi Uchida^1,3,4, Yuya Sakuraba^1,5 (1.NIMS, 2.CSRN, Osaka Univ., 3.IMR, Tohoku Univ., 4.CSRN, Tohoku Univ., 5.JST PRESTO)

Keywords:transverse thermoelectric generation, anomalous Nernst effect, Heusler alloy

The anomalous Nernst coefficient (S_ANE) can be separated into two components as S_ANE = ρ_xxα_xy − ρ_AHEα_xx, where ρ_xx is the longitudinal resistivity, ρ_AHE is the anomalous Hall resistivity, and α_xx and α_xy are the diagonal and off-diagonal components of the Peltier tensor, respectively. The second term on the right hand side can be rewritten as – S_SE × ρ_AHE / ρ_xx, indicating it originates from the anomalous Hall effect (AHE) of the longitudinal carrier flow induced by SE, and S_SE is the Seebeck coefficient. Here, inspired by the second term, we propose a different approach for transverse thermoelectric generation. We consider a system that consists of a thermoelectric material and a magnetic material electrically connected at both ends along the ∇T direction to form a closed circuit. The large electric field generated by SE of the thermoelectric material was converted to transverse thermoelectric generation by AHE of the magnetic material, which showed a similar symmetry to anomalous Nernst effect, but surprisingly, potential for a colossal enhancement in thermopower. This is referred to as the Seebeck-driven transverse thermoelectric generation (STTG).