共查询到17条相似文献,搜索用时 62 毫秒
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稀磁半导体(DMSs)材料同时利用了电子的电荷属性和自旋属性,具有优异的磁、磁光、磁电等性能,在材料学和未来自旋电子器件领域具有广阔的应用前景。本文综合述评了近几年来ZnO基稀磁半导体纳米材料研究的进展概况,并简介了DMSs器件的潜在应用。 相似文献
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主要介绍了AlN基稀磁半导体(DMS)的研究进展,包括其发展过程、AlN基DMS的研究现状,描述了理想的AlN基DMS材料应具备的特征,并展望了其未来的研究方向. 相似文献
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稀磁半导体制备方法与磁性起源的研究是当前凝聚态物理的一项热门课题.首先介绍了自燃烧合成法的原理和优点,然后以Co和Mn掺杂ZnO为重点,总结了国内外采用自燃烧法合成的ZnO基稀磁半导体纳米颗粒晶体结构、磁性能相关的研究进展,讨论了所得纳米颗粒磁性能的内在物理机制.通过对自燃烧法合成的更宽掺杂范围ZnO基稀磁半导体纳米颗粒的研究,使我们能够更加系统地了解过渡金属掺杂ZnO材料的结构与磁性能,并探讨所得实验现象的内在物理机制. 相似文献
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We calculated the chemical trends of transition metal-doped chalcopyrite DMS (diluted magnetic semiconductors) by the use of KKR–CPA–LDA method. The ferromagnetism was stable in V- and Cr-doped chalcopyrite DMS. In the case of Fe and Co doping, however, the spinglass-like state was realized. On the other hand, in the cases of Mn doped I-III-VI2 and II-IV-V2 type DMS, the ground state was ferromagnetic and spinglass-like, respectively. 相似文献
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We investigated the transport and optical properties of diluted magnetic semiconductors theoretically by using a simple model where carriers move in a single band. In this model the carrier feels a nonmagnetic potential at a magnetic impurity site, and its spin interacts with the localized spins of the magnetic impurities through exchange interactions. The electronic states of a carrier were calculated by using the coherent potential approximation (CPA). The magnetism was investigated by minimizing the free-energy and the electrical conductivity was calculated by using the Kubo formula. We examined the results in several typical cases which correspond to (Ga1–xMnx)As with x = 0.05. 相似文献
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O. Mounkachi M. Boujnah H. Labrim M. Hamedoun A. Benyoussef A. El Kenz M. Loulidi B. Belhourma M. Bhihi E. K. Hlil 《Journal of Superconductivity and Novel Magnetism》2012,25(5):1515-1521
Structural and magnetic properties of Zn0.8(Fe0.1, Co0.1)O bulk diluted magnetic semiconductor have been investigated using X-ray diffraction (XRD) and magnetic measurements. TEM (Transmission Electron Microscopy) images confirmed the high crystallinity and grain size of Zn0.8(Fe0.1,Co0.1)O powder, the samples were characterized by energy dispersive spectroscopy (EDS) to confirm the expected stoichiometry. This sample has been synthesized by co-precipitation route. The study of magnetization hysteresis loop measurements infers that the bulk sample of Zn0.8(Fe0.1,Co0.1)O shows a well-defined hysteresis loop at T c (200?K) temperature, which reflects its ferromagnetic behavior. Hydrogenation treatment was used for the control of phase separation. Based on first-principles spin-density functional calculations, using the Korringa?CKohn?CRostoker method (KKR) combined with the coherent potential approximation (CPA), the ferromagnetic state energy was calculated and compared with the local-moment-disordered (LMD) state energy. The mechanism of hybridization and interaction between magnetic ions in Zn0.8(Fe0.1,Co0.1)O is also investigated. 相似文献
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ZnO是一种宽带隙Ⅱ-Ⅵ族半导体,具有良好的光电耦合特性和稳定性,在光、电、磁功能集成等新型器件方面可获得重要应用.近来的研究表明,过渡金属掺杂的ZnO基半导体有望成为实现高居里温度稀磁半导体的候选材料,是目前研究的热点.总结了近几年人们在Fe、Co、Ni、Cu、Mn等过渡金属掺杂的ZnO基稀磁半导体的发光特性研究结果,讨论了过渡金属掺杂后ZnO中观察到的可见发光机制,分析认为过渡金属掺杂ZnO的可见光发射主要与这些发光过渡金属引入后所产生的缺陷有关,而紫外发光峰的变化则与过渡金属掺入后ZnO晶体质量与禁带宽度的改变相关. 相似文献
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This paper, based on a presentation at the Spintronics 2001 conference, provides a review of our studies on II–VI and III–V Mn-doped Diluted Magnetic Semiconductors. We use simple models appropriate for the low carrier density (insulating) regime, although we believe that some of the unusual features of the magnetization curves should qualitatively be present at larger dopings (metallic regime) as well. Positional disorder of the magnetic impurities inside the host semiconductor is shown to have observable consequences for the shape of the magnetization curve. Below the critical temperature the magnetization is spatially inhomogeneous, leading to very unusual temperature dependence of the average magnetization as well as specific heat. Disorder is also found to enhance the ferromagnetic transition temperature. Unusual spin and charge transport is implied. 相似文献
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J. Kudrnovský I. Turek V. Drchal F. Máca J. Maek P. Weinberger P. Bruno 《Journal of Superconductivity》2003,16(1):119-122
The Curie temperature of diluted (Ga,Mn)As magnetic semiconductors in the presence of As antisites is studied from first principles. We map total energies associated with rotations of Mn-magnetic moments onto the effective classical Heisenberg Hamiltonian which is treated in the mean-field approximation to find the Curie temperature. The presence of donors strongly reduces the Curie temperature and gives rise to a ground state with a partial disorder of local moments. We show that the observed dependence of the Curie temperature on the Mn concentration indicates that the concentration of As antisites increases with the Mn content. 相似文献