Spin polarized transports through a narrow-gap semiconductor wire with ferromagnetic contacts formed on InAlAs step-graded buffer layers

详细信息    查看全文

• 作者：Akabori ; Masashi ; Yamada ; Syoji
• 关键词：InAs ; InAlAs ; 2DEG ; Step-graded buffer ; Ferromagnetic electrodes ; Spin polarized transports
• 刊名：Science and Technology of Advanced Materials
• 出版年：2004
• 出版时间：May, 2004
• 年：2004
• 卷：5
• 期：3
• 页码：305-308
• 全文大小：205 K

文摘

We investigated the transport properties of ferromagnetic/semiconductor hybrid structures utilizing an InAs/In_0.75Al_0.25As modulation-doped heterostructures formed on a GaAs (001) substrate with In_xAl_1−xAs step-graded buffer layers. We used NiFe as ferromagnetic electrodes for injection/detection of spin-polarized electrons, which were formed on side walls of the semiconductor mesa to contact electron channel directly. We measured magneto-transport properties of the samples with current flow between the ferromagnetic electrodes at low temperatures. Under vertical magnetic fields, magneto-resistance oscillations were clearly observed, thus the ferromagnetic electrodes worked as ohmic contacts. In addition, we successfully found spin-valve properties under parallel magnetic fields. Furthermore, we observed the enhancement of spin-valve properties by squeezing the channel width.