Semiconductor-baaed magneto-photonic crystals and their applications

半导体磁光子晶体及其应用

基本信息

批准号：
14205003
负责人：
TANAKA Masaaki
金额：
$ 32.61万
依托单位：
The University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
2002
资助国家：
日本
起止时间：
2002 至 2005
项目状态：
已结题

项目摘要

We have successfully grown a new quaternary alloy magnetic semiconductor (InGaMn)As, and have found that it is ferromagnetic with T_c〜130K. In (InGaMn)As, the lattice constant and the bandgap can be changed, and it can be grown on lattice-matched InP substrates, thus having good compatibility with optical communication devices. More recently, we have realized high T_c of 172-250K in Mn-delta-doped GaAs/p-AlGaAs heterostructures, which are the highest values ever reported in III-V based materials. Recently, we find out the giant planar Hall effect in Mn-delta-doped GaAs/p-AlGaAs heterostructures and clarified the magnetic anisotropy. Such new magnetic quantum heterostructures are very attractive in view of fundamental research as well as potential applications to "spintronics".Recently, we observed negative TMR and oscillations of the TMR ratio (with varying the AlAs thickness) in GaMnAs/AlAs/InGaAs/AlAs/GaMnAs double-barrier ferromagnetic tunnel junctions, for the first time in magneti … More c semiconductor systems. This is caused by the appearance of resonant tunneling and TMR effects at the same time. Realization of such large spin-dependent tunneling in semiconductor heterostructures, that is spin injection from one semiconductor layer to another semiconductor layer via tunneling, is an very significant step towards future spintronics, in which one tries to use the spin degree of freedom in semiconductor devices.We have fabricated ferromagnet(MnAs)/III-V semiconductor(GaAs) granular structures, hereafter GaAs : MnAs, by annealing (GaMn)As at 500-800℃. During the annealing process, MnAs ferromagnetic clusters with diameters of a few nm were formed in a matrix of GaAs (or GaMnAs), exhibiting a superparamagnetic behavior. We have established the fabrication process and have measured magneto-optic properties. Furthermore, we have fabricated GaAs:MnAs sandwiched by GaAs/AlAs distributed Bragg Reflectors (DBRs), and have showed significant enhancement of magneto-optical effect by using multiple interference and localization of light in the GaAs:MnAs magnetic layer. This structure offers new opportunity for the application to spin-controlled photonic devices based on III-V compound semiconductors. Recently, we have found extremely large positive magnetoresistance of 600 % at room temperature in the GaAs:MnAs granular structures, and further investigations are underway. Less

我们已经成功地种植了新的Quaternary磁性半导体（INGAMMN）为AMN），可以更改晶格和带隙，并且可以在晶格匹配的INP底物上生长，从而与通信设备具有良好的兼容性n Mn-Delta掺杂的GAA/P-AlgaAAS异质结构，这是基于III-V的材料中报告的最高值。磁铁螺旋镜。鉴于基本研究以及潜在的约会，我们的第一个磁性量子异质结构也非常有吸引力的，并且潜在的约会也是“旋转的”。在磁铁中的时间……更多的C半导体系统。）颗粒状结构，以下是GAAS：MNA，通过500-800°C退火（GAMN）。在退火过程中，在GAAS（或GAMNAS）的矩阵中形成了几个NM的MNA Ferromagnetic簇建立了制造过程，并测量了磁化特性。 - 基于III-V组合半导体的控制光子设备在GAAS中的温度下为600％：MNAS颗粒结构和进一步的投资正在进行中。