Study of Spin Injection from Fe3Si into GaAs by Spin Light-Emitting-Diode

• Main Authors: Li, Yi-Sheng, 李奕昇
• Other Authors: Kwo, Raynien
• Format: Others
• Language: en_US
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/65673134454423808154

碩士 === 國立清華大學 === 物理學系 === 97 === The spin-polarized light-emitting diode (spin-LED) is a very powerful means for accurately quantifying spin injection through detecting left and right circular polarized light. It is difficult to maintain the spin polarization injected from a ferromagnetic metal into a semiconductor. The spin polarized electron would combine with un-polarized hole and generate circular polarized light at quantum well. In this work, we have investigated the spin-LEDs made of Fe3Si/GaAs heterostructures. Fe3Si, as a Heusler alloy, is expected to be half metal with 100% spin polarization at the Fermi level, thus making Fe3Si an attractive material for spin injection. The spin-LED was deposited by in-situ multi-chamber MBE system. Furthermore, we have detected the circular polarization by a home-built low temperature measurement system which we set up. In the future, we plan to measure the higher and closer the spin polarization which was generated from Fe3Si.