Study on magnetism at conducting interfaces in nonmagnetic oxides

2016 Fiscal Year Final Research Report

• Project/Area Number: 26390059
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Thin film/Surface and interfacial physical properties
• Research Institution: Tohoku University
• Principal Investigator: Nojima Tsutomu 東北大学, 金属材料研究所, 准教授 (80222199)
• Research Collaborator: OUCHI Takumi ; TANAKA Shun
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: 酸化物エレクトロニクス / 電界効果 / 電気二重層トランジスタ / ２次元電子系 / スピン軌道相互作用

Outline of Final Research Achievements

We studied magnetic properties of two dimensional electron systems at SrTiO3 (001) surfaces，which were induced by electric field in the electric double layer transistor (EDLT) device　configurations. While SrTiO3 is a well-known nonmagnetic oxide in bulk, the surface electron system of it with the carrier densities higher than 0.15 per one unit cell area shows the anisotropic magnetoresistance and the planar Hall effects, which are usually observed in ferromagnetic thin films. Through the detailed measurements of magnetization and in-plane anisotropy of magnetotransports, controlled by the gate voltage in the EDLT devices, we found that the observed magnetic properties do not caused by the ferromagnetic order but results from the spin alignment phenomena with a special spin texture, originating from a Rashba-type spin-orbit coupling enhanced with multi-orbital hybridization effect in Ti-3d electrons.

Free Research Field

低温物理学