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arXiv 1003.2498cond-mat.str-el
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无序时的关联电子

Correlated electrons in the presence of disorder

K. Byczuk, W. Hofstetter, U. Yu, D. Vollhardt

摘要:

电子关联和无序之间的微妙的相互作用的几个新的方面进行了审查。首先,利用动力学平均场论(DMFT)和几何平均(“典型”)局域态密度计算了Anderson-哈伯德模型在半填充时的基态相图。这种非微扰方法在单粒子水平上对安德森局域化敏感,因此可以检测到相关的金属相、Mott绝缘相和安德森绝缘相,也可以描述安德森局域化与反铁磁性之间的竞争.其次,我们研究了二元合金无序对周期性Anderson模型描述的含$f$ -电子材料铁磁性的影响。居里温度$T_c$的急剧增强所造成的增加的本地$f$ -时刻在无序导电电子的存在下被发现和解释。

英文摘要:

Several new aspects of the subtle interplay between electronic correlations and disorder are reviewed. First, the dynamical mean-field theory (DMFT)together with the geometrically averaged ("typical") local density of states is employed to compute the ground state phase diagram of the Anderson-Hubbard model at half-filling. This non-perturbative approach is sensitive to Anderson localization on the one-particle level and hence can detect correlated metallic, Mott insulating and Anderson insulating phases and can also describe the competition between Anderson localization and antiferromagnetism. Second, we investigate the effect of binary alloy disorder on ferromagnetism in materials with $f$-electrons described by the periodic Anderson model. A drastic enhancement of the Curie temperature $T_c$ caused by an increase of the local $f$-moments in the presence of disordered conduction electrons is discovered and explained.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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