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The Magnetic Study of Zinc Oxide-based Diluted Magnetic Semiconductors

Author: HeChun
Tutor: WangJinBin
School: Xiangtan University
Course: Materials Physics and Chemistry
Keywords: Zinc oxide - based diluted magnetic semiconductor Ferromagnetic RKKY exchange interaction Superexchange interactions Double exchange interaction
CLC: O482.5
Type: Master's thesis
Year: 2009
Downloads: 114
Quote: 0
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Abstract


Dilute magnetic semiconductor material is an important branch of the field of spintronics, evolved based diluted magnetic semiconductor materials spintronic devices while taking advantage of the electronic charge and spin properties of quantum mechanics bottlenecks faced by traditional electronics can break information transfer, processing and storage in one extensive attention by the scientific community. The zinc oxide (Zinc Oxide, ZnO) is a wide band gap Group II-VI compound semiconductor, has wide application in the field of optoelectronic devices of the transmission FET, a light emitting diode, a solar cell, etc.. ZnO based diluted magnetic semiconductors (DMS) Curie temperature above room temperature because of its theoretical predictions widespread concern, but the understanding of the modulation of the magnetic ZnO-based DMS, will be based on the development of a new generation of non-volatile dilute magnetic semiconductor transistor important experimental and theoretical basis. This paper on the the magnetic studies ZnMnO system, ZnCoO the system, ZnNiO system to understand the influencing factors of magnetism in ZnO-based DMS mainly include the following aspects: 1. System, on ZnMnO, the main consideration RKKY interaction between magnetic atoms and super-exchange interaction as a result, the system of the magnetic and the magnetic atoms doping concentration, the carrier concentration, RKKY-interaction and super-exchange interaction, the magnetization of the system with the increase of the RKKY exchange interaction coefficients J0 increases, along with the increase of the exchange interaction coefficient k decreases. And with the magnetic atoms doping concentration increases, the system to achieve a higher magnetization will require a larger carrier concentration. 2. System of ZnCoO, the main consideration RKKY interaction between magnetic atoms and superexchange interactions, and found that the magnetization of the system first increases with increasing carrier concentration decreases, the magnetization of the system RKKY exchange interaction and the superexchange interaction between competition-related. The magnetic susceptibility of the system change with temperature relationship results: at the lower temperature, the magnetic susceptibility of the system is large, and the magnetic susceptibility of the system decreases with increasing temperature while the rate of change of decreasing J0 value increases with the increase of the values ??of k increases. 3. System of ZnNiO, mainly consider three spin exchange interactions: the super-exchange interaction, the double exchange interaction and the RKKY exchange interaction, the magnetization of the system increases as the double exchange interaction parameter t value increases, with the the RKKY exchange effect coefficient of J0 increase increases, decreases as the super-exchange interaction coefficients k increases. The magnetic susceptibility of the system change with temperature relationship as follows: the rate of change of the magnetic susceptibility of the system decreases with increasing temperature and with decreasing J0 value increases with the increase of the value of k is increased, with The reduction of the value of t is increased within a certain carrier concentration range, the rate of change decreases with increasing carrier concentration.

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CLC: > Mathematical sciences and chemical > Physics > Solid State Physics > Solid nature of the > Magnetic properties
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