[3Ga01-10] Surface Science(SS1) Physical Property

[3Ga10] Adsorption, intercalation and spin injection at the surface of Bi₂Se₃ thin films by spin-polarized hydrogen atomic beam

*Yusei Ohashi¹, Takahiro Ozawa¹, Hirokazu Ueta², Hiroyuki Koshida¹, Markus Wilde¹, Katsuyuki Fukutani^1,2 (1. Institute of Industrial Science, the University of Tokyo., 2. Advanced Science Research Center, Japan Atomic Energy Agency)

Bi₂Se₃ is one of the typical three-dimensional topological insulators, which have metallic surface states with spin-momentum locked. When a spin current flows through such a surface state, the spin current is converted into an electric current, which is known as the inverse Edelstein effect. We have developed a spin-polarized atomic hydrogen beam that can select a single electron spin state. First, we conducted the analyses of structural changes and hydrogen desorption characteristics of atomic-hydrogen-exposed Bi₂Se₃ thin films. Based on the LEED and TDS results and the previous theoretical study, it is suggested that atomic hydrogen exposure to Bi₂Se₃ at 295 K results in hydrogen adsorption only on the surface, while at 90 K, hydrogen intercalation between the QLs occurred in addition to hydrogen adsorption. Finally, we report on the results of spin injection into Bi₂Se₃ thin films using a spin-polarized hydrogen atom beam.