[16p-S2_201-1~11] 10.4 Spintronics in semiconductor, topological material, superconductor, and multiferroics

4:15 PM - 4:30 PM JST(7:15 AM - 7:30 AM UTC)Presentation by Applicant for JSAP Young Scientists Presentation AwardEnglish Presentation

[16p-S2_201-9] Magnetic-Proximity-Modulated Spin–Charge Conversion in Ferromagnetic Metal Fe / Topological Dirac Semimetal α-Sn Heterostructures

〇(M2)Masayuki Ishida¹, Soichiro Fukuoka¹, Takahiro Chiba^3,4, Yohei Kota⁵, Masaaki Tanaka^1,2,6, Anh Le Duc^1,2 (1.Univ. of Tokyo, 2.CSRN, 3.Yamagata Univ., 4.Tohoku Univ., 5.NIT Fukushima, 6.NanoQuine)

Keywords:

spin-charge conversion,topological Dirac semimetal,alpha-Sn

Spin-to-charge conversion (SCC) experiments at room temperature were performed using spin pumping in ferromagnetic Fe (4 nm) / topological Dirac semimetal α-Sn (9–35 nm) / InSb(001) heterostructures grown by molecular beam epitaxy. An enhancement of the Gilbert damping constant, evidencing spin injection, was observed in all samples containing α-Sn. A pronounced voltage signal was detected for the sample with a 25 nm α-Sn layer, demonstrating efficient SCC with a maximum inverse Edelstein length of λ_IEE≈ 3.1 nm, which represents a world-record efficiency at room temperature. Analysis of the α-Sn thickness dependence, combined with DFT calculations and theoretical modelling, reveals that a magnetic-proximity-induced surface band gap in the topological surface state (TSS) of α-Sn plays a crucial role in governing the SCC efficiency. These results underscore the importance of controlling TSS via magnetic proximity effects for achieving highly efficient spin-to-charge conversion.