The 69th JSAP Spring Meeting 2022

Presentation information

Oral presentation

10 Spintronics and Magnetics » 10.4 Spintronics in semiconductor, topological material, superconductor, and multiferroics

[23p-E205-1~18] 10.4 Spintronics in semiconductor, topological material, superconductor, and multiferroics

Wed. Mar 23, 2022 1:30 PM - 6:30 PM E205 (E205)

Jun Okabayashi(Univ. of Tokyo), Hiroshi Katayama-Yoshida(Univ. Tokyo), Eisuke Abe(Riken)

4:15 PM - 4:30 PM

[23p-E205-11] Giant spin-to-charge conversion in an all-epitaxial single-crystal-oxide Rashba LaTiO3+δ/SrTiO3 heterostructure

〇(D)Shingo Kaneta1, Miho Kitamura2, Shoma Arai1, Takuma Arai1, Ryo Okano1, Le Duc Anh1,3,4, Tatsuro Endo1, Koji Horiba2, Hiroshi Kumigashira2,5, Masaki Kobayashi1,6, Munetoshi Seki1,6, Hitoshi Tabata1,6, Masaaki Tanaka1,6, Shinobu Ohya1,3,6 (1.Univ. of Tokyo, 2.KEK, 3.IEI, Univ. of Tokyo, 4.PRESTO, JST, 5.IMRAM, Tohoku Univ., 6.CSRN, Univ. of Tokyo)

Keywords:Spin-to-charge conversion, Two-dimensional electron gas, Oxide heterostructure

The two-dimensional electron gas (2DEG) formed at oxide interfaces, such as LaAlO3/SrTiO3 (STO) and AlOx/STO, has attracted much attention for their extremely large spin-to-charge conversion efficiencies λIEE up to ~60 nm due to the large Rashba spin-orbit interaction. However, these insulating layers on STO prevent the propagation of a spin current injected from an adjacent ferromagnetic layer. Moreover, the mechanism of the spin-current flow in these insulating layers is still unexplored. Here, using a strongly correlated polar-metal LaTiO3+δ (LTO) interlayer and the 2DEG formed at the LTO/STO interface in an all-epitaxial heterostructure, we demonstrate giant λIEE up to ~190 nm. The obtained λIEE is the highest value among those reported for all materials including metals, semiconductors, and topological systems so far. This highly efficient spin transport/conversion highlights the new hidden inherent possibilities of oxide interfaces for spin-orbitronics applications.