[15a-A501-1~13] 10.1 Emerging materials in spintronics and magnetics (including fabrication and charactrization methodologies)

▼ [15a-A501-1] Observation of Weyl Cones in Ferromagnetic Heusler Alloy Films Co₂MnGa by Spin- and Angle-Resolved Photoemission Spectroscopy

〇(P)Kazuki Sumida¹, Yuya Sakuraba², Keisuke Masuda², Takashi Kono³, Masaaki Kakoki³, Kazuki Goto², Koji Miyamoto⁴, Yoshio Miura², Taichi Okuda⁴, Akio Kimura³ (1.Tokyo Tech., 2.NIMS, 3.Hiroshima Univ., 4.HSRC)

Keywords:Heusler alloy, Weyl semimetal, Photoemission spectroscopy

Weyl semimetals are characterized by massless band dispersion in momentum space. When the Weyl semimetals meet magnetism, large anomalous transport properties would emerge due to their topological nature. In this study, we visualize the spin-polarized Weyl cone evolved from nodal lines of the film form of ferromagnetic Co₂MnGa with full remanent magnetization by using in-situ spin- and angle-resolved photoemission spectroscopy and ab initio calculations. We also demonstrate that the anomalous Hall and Nernst conductivities grow when the Weyl node approaches the Fermi energy, and the highest anomalous Nernst thermopower ~6.2 μV/K is realized at room temperature among ferromagnetic films.