Fe-based carrier-induced ferromagnetic semiconductors and their applications to next-generation spin devices

2014 Fiscal Year Final Research Report

• Project/Area Number: 24686040
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Partial Multi-year Fund
• Research Field: Electronic materials/Electric materials
• Research Institution: Tokyo Institute of Technology (2014); The University of Tokyo (2012-2013)
• Principal Investigator: PHAM NAM HAI 東京工業大学, 理工学研究科, 准教授 (50571717)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 強磁性半導体 / 量子効果 / スピントロ二クス

Outline of Final Research Achievements

In this research, we aimed at fabrication of new Fe-based ferromagnetic semiconductors and development of new spin-devices utilizing them. The major results are as follows. First, we successfully fabricated (1) the world’s first n-type electron-induced ferromagnetic semiconductor (In,Fe)As. We observed (2) the quantum-size effect in quantum wells with ultrathin (In,Fe)As layers. We successfully controlled ferromagnetism by controlling the overlapping between Fe atoms and electron wavefunctions in spin-transistor structures with (In,Fe)As quantum wells for the first time. We then fabricated (3) a new p-type ferromagnetic semiconductor (Ga,Fe)Sb, and improved the Curie temperature of this material up to 230 K, which is the highest value ever reported for intrinsic ferromagnetic semiconductors. Our results indicate that Fe-based ferromagnetic semiconductors are very promising materials for semiconductor spintronics.

Free Research Field

スピントロ二クス