The 81st JSAP Autumn Meeting, 2020

Presentation information

Oral presentation

9 Applied Materials Science » 9.4 Thermoelectric conversion

[8p-Z18-1~16] 9.4 Thermoelectric conversion

Tue. Sep 8, 2020 12:30 PM - 5:15 PM Z18

Mikio Koyano(JAIST), Takahiro Tomita(東大), Takafumi Ishibe(Osaka Univ.)

4:30 PM - 4:45 PM

[8p-Z18-14] Anomalous Nernst effect under in- and out-of-plane heat flux in the Weyl ferromagnet Co2MnGa thin films

〇(M2)Ryota Uesugi1, Tomoya Higo1,2, Zheng Zhu1, Kouta Kondou2,3, Akito Sakai2,4, Mihiro Asakura4, Yoshichika Otani1,2,3,5, Satoru Nakatsuji1,2,4,5,6 (1.ISSP, Univ. of Tokyo, 2.JST CREST, 3.RIKEN CEMS, 4.Univ. of Tokyo, 5.Trans-Quantum Science Inst., Univ. of Tokyo, 6.Johns Hopkins Univ.)

Keywords:Nernst effect, Heusler alloy, Topological magnet

Anomalous Nernst effect (ANE) can generate an electromotive force perpendicular to the heat flux, which provide a technological potential for film-based thermoelectric devices. However, the conversion efficiency was thought that be limited to around 1 μV/K, which is hundred times smaller than the Seebeck coefficient obtained in conventional thermoelectric materials because it is depended on their own magnetization. Recently, we found that the non-collinear Weyl anti-ferromagnet Mn3Sn and full-Heusler Weyl ferromagnet Co2MnGa show the large ANE 0.35 and 6 μV/K respectively due to a large Berry curvature from Weyl points working as a fictitious magnetic field in the momentum space. We fabricated the Weyl ferromagnet Co2MnGa thin films by DC magnetron sputtering and report ANE under in-plane and out-of-plane heat flux.