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arXiv 1507.04360cond-mat.str-el
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Mott金属-绝缘体相变附近的安德森局域化效应

Anderson localization effects near the Mott metal-insulator transition

Helena Braganca, M. C. O. Aguiar, J. Vucicevic, D. Tanaskovic, V. Dobrosavljevic

摘要:

在无序相互作用系统中,Mott和Anderson的局域化路线之间的相互作用产生了不同的跃迁和输运机制。本文采用动力学平均场论结合Mott-Anderson金属-绝缘体相变的有效理论--典型介质理论研究了有限温度下的相图。我们主要关注与Mott相变相关的共存区的性质。对于弱无序,共存区域被发现是在干净的情况下类似。然而,当我们增加无序安德森局域化效应是负责收缩的共存区域,并在足够强的无序(约等于两倍的裸带宽),它急剧变窄,临界温度突然变为零,我们观察到一个相变的金属和绝缘相共存的情况下。在这一制度中,相互作用和无序的影响被认为是相当重要的电荷本地化。

英文摘要:

The interplay between Mott and Anderson routes to localization in disordered interacting systems gives rise to different transitions and transport regimes. Here, we investigate the phase diagram at finite temperatures using dynamical mean field theory combined with typical medium theory, which is an effective theory of the Mott-Anderson metal-insulator transition. We mainly focus on the properties of the coexistence region associated with the Mott phase transition. For weak disorder, the coexistence region is found to be similar as in the clean case. However, as we increase disorder Anderson localization effects are responsible for shrinking the coexistence region and at sufficiently strong disorder (approximately equal to twice the bare bandwidth) it drastically narrows, the critical temperature abruptly goes to zero, and we observe a phase transition in the absence of a coexistence of the metallic and insulating phases. In this regime, the effects of interaction and disorder are found to be of comparable importance for charge localization.

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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