稀土掺杂钙钛矿锰氧化物CMR效应的研究毕业设计.doc

稀土掺杂钙钛矿锰氧化物CMR效应的研究 摘 要 近年来,具有庞磁电阻效应的稀土掺杂锰氧化物成为了凝聚态物理研究的重要领域。锰氧化物的载流子自旋极化率高,且在居里温度附近表现出很大的磁电阻效应,因此在自旋电子学中有潜在的应用前景。另一方面,锰氧化物是典型的强关联电子体系,它对目前有关强关联体系的认识提出了很大挑战。目前，掺杂稀土元素对钙钛矿锰氧化物的庞磁电阻效应有着重要的影响，本文综述了锰氧化物的各种性质及其物理原因以及在稀土中掺杂钙钛矿锰氧化物对庞磁电阻效应的影响，并且讨论了锰氧化物的一些可能的应用以及对庞磁电阻材料的展望。 关键词：锰氧化物；CMR效应；相分离；磁电阻；双交换作用 The Study of CMR Effect of Perovskite Manganese Oxide Dopes Rare Earth Abstract In recent years, the Manganese oxide which dopes rare earth with Le pen magnetoresistance effct has become the imortant part of Condensed matter physics research. On the one hand, Manganese oxide carrier spin polarization rate is high and it shows a large Magnetoresistance effect near the Curie temperature. Therefore it has potential applications in spintronics. On the other hand, Manganese oxide is a typical strongly correlated electron system, and it puts forward a great challenge to the strong correlation system. At present, the doping of rare earth elements on the Colossal Magnetoresistance Perovskite manganite resistance effect has an important effect. The paper not only reviews the various properties of the manganese oxide, its physical reasons and the effect of Perovskite manganese oxide mixed with rare earth to the Le pen magnetoresistance , but also discusses the possible applications of the manganese oxide, as well as the outlook for the Colossal magnetoresistance materials. Key words: Manganese oxide; CMR effect; Phase separation; Magnetoresistance; Double exchange interaction 目 录 TOC \o 1-4 \h \z \u HYPERLINK \l _Toc323803756 1. 钙钛矿锰氧化物基本物理性质 PAGEREF _Toc323803756 \h 1 HYPERLINK \l _Toc323803757 1.1 钙钛矿锰氧化物基本的晶格 PAGEREF _Toc323803757 \h 1 HYPERLINK \l _Toc323803758 1.2 钙钛矿锰氧化物电子结构和电子态 PAGEREF _Toc323803758 \h 2 HYPERLINK \l _Toc323803759 1.3 层状钙钛矿锰氧化物的磁性和电性 PAGEREF _Toc323803759 \h 3 HYPERLINK \l _Toc323803760 2. 钙钛矿锰氧化物涉及的一些基本理论 PAGEREF _Toc323803760 \h 5 HYPERLINK \l _Toc323803761 2.1 双交换相互作用 PAGEREF _Toc323803761 \h 5 HYPERLINK \l _Toc323803762 2.2 氧化物中的相分离 PAGEREF