High efficiency spin injection and low loss spin transport in diamond semiconductors

2018 Fiscal Year Final Research Report

• Project/Area Number: 16H04348
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Electron device/Electronic equipment
• Research Institution: Nagoya University
• Principal Investigator: Ueda Kenji 名古屋大学, 工学研究科, 准教授 (10393737)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: ダイヤモンド / 半導体 / スピン注入

Outline of Final Research Achievements

In this study, we have tried highly efficient spin injection and low loss spin transport in diamond semiconductors. Spin injection efficiency into diamond became one order larger than that before by tuning surface-termination state of diamond and improving crystal quality of tunnel barriers in magnetic tunnel junctions on diamond. We have succeeded in fabricating epitaxial Mn2CoAl films, which are spin gapless semiconductors (SGS), at lower growth temperature and observed ambipolar characteristics, which is one of main characteristics of SGS. We have succeeded in fabricating graphene layers on diamond, that is important for efficient spin injection, and also found graphene/diamond junctions showed peculiar conductivity change by photo irradiation.

Free Research Field

薄膜機能材料

Academic Significance and Societal Importance of the Research Achievements

スピン注入源となる磁性トンネル接合とダイヤモンド界面を、ダイヤモンドの表面終端を含めて精密に制御する事がダイヤモンドへの高効率スピン注入に必須となる事を見出した。また、ダイヤモンドとグラフェン積層・複合化し、炭素sp2/sp3界面を創製する事で新たな機能が発現する事が分かった。