Semiconductor-baaed magneto-photonic crystals and their applications

半导体磁光子晶体及其应用

• 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
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-14205003/
• 关键词: semiconductor magneto-photonic crystals; spin; magneto-optical effect; MnAs; GaMnAs; InGaMnAs; tunneling magnetoresistance; waveguide-type optical isolator; 磁気光学結晶; 強磁性半導体; キュリー温度; クラスター; 分子線エピタキシー; 強磁性ナノクラスター; スピントロニクス; semiconductor magneto-photonic crystals; spin; magneto-optical effect; MnAs; GaMnAs; InGaMnAs; tunneling magnetoresistance; waveguide-type optical isolator; 磁気光学結晶; 強磁性半導体; キュリー温度; クラスター; 分子線エピタキシー; 強磁性ナノクラスター; スピントロニクス

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一种新的四元合金磁性半导体（INGAMN），并发现它具有T_C〜130K的铁磁。在（Ingamn）AS中，可以更改晶格常数和带隙，并且可以在晶格匹配的INP底物上生长，从而与光学通信设备具有良好的兼容性。最近，我们已经实现了Mn-Delta掺杂的GAAS/P-AlgaAS异质结构中的172-250k的高T_C，这是基于III-V的材料中有史以来最高的值。最近，我们发现了Mn-Delta掺杂的GAAS/P-AlgaAS异质结构中的巨型平面厅效应，并阐明了磁各向异性。鉴于基本研究以及对“旋转器”的潜在应用，这种新的磁量子异质结构非常有吸引力。我们观察到TMR比（在GAMNAS/ALAS/ALAS/ALAS/INGAAS/INGAAS/ALAS/ALAS/GAMNAS DOUPHANAS DOBLERIER FEREROTION HEMITION INTERY TURENTIRE TURENTIRE TURENTIRE TUMITY CANCTITY）中，TMR比（可与厚度变化不同）的负TMR和振荡系统。这是由于同时出现谐振隧道和TMR效应引起的。通过隧穿从一个半导体层到另一个半导体层的自旋注射在半导体异质结构中实现如此大的自旋依赖性隧穿，这是朝着将来的SpinTronics迈出的极为重要的一步，其中一个尝试在半导体中使用半导体设备中的自由度。此后GAAS：MNA，通过500-800℃退火（Gamn）。在退火过程中，在GAAS（或GAMNAS）的基质中形成了具有直径为几个nm的MNA铁磁簇，表现出超顺磁行为。我们已经建立了制造过程，并测量了磁化特性。此外，我们已经制造了GAAS：由GAAS/Alas分布的Bragg反射器（DBRS）夹紧的MNA，并通过使用GAAS中的光的多重干扰和局部定位显示了磁光学效应的显着增强：MNAS磁性层。该结构为基于III-V复合半导体的自旋控制光子设备的应用提供了新的机会。最近，我们发现在GAAS中的室温下，在室温下的正势力极大，即MNA颗粒结构，并正在进行进一步的研究。较少的