[9a-E208-1~5] 10.1 Emerging materials in spintronics and magnetics (including fabrication and characterization methodologies)

9:15 AM - 9:30 AM JST(12:15 AM - 12:30 AM UTC)Presentation by Applicant for JSAP Young Scientists Presentation AwardEnglish Presentation

[9a-E208-2] Synthesis of epitaxial RuSi thin films and exploration of their Zak-phase surface states

〇Koma Miki^1,2, Takahiro Iwagaki^1,2, Hideki Matsuoka¹, Naoya Kanazawa¹ (1.IIS, Utokyo, 2.Grad. Sch. of Eng., UTokyo)

Keywords:

topological surface state,epitaxial thin films,surface ferromagnetism

The Zak phase, a bulk band-topological quantity, defines a class of insulators that host characteristic surface states. A striking example is B20-type FeSi, whose nonmagnetic insulating bulk supports a ferromagnetic metallic surface state with a giant Rashba splitting despite consisting solely of light elements. We extend this principle to B20-type RuSi, in which the 4d element ruthenium occupies the Fe site, with reduced electron correlation and enhanced SOC. Using a buffer layer, we have achieved single-phase epitaxial growth of RuSi(111) thin films by molecular beam epitaxy, previously unrealized due to competing stable phases. The thin films exhibit magnetotransport indicative of an emergent ferromagnetic metallic surface state, which we discuss in relation to the surface electronic and spin states.