近日,德国马克斯普朗克固体研究院的Thomas Schafer及其研究小组与美国哥伦比亚大学的Andrew J.Millis等人合作并取得一项新进展。经过不懈努力,他们对莫尔过渡金属二硫化物的磁性和金属丰度进行研究
在本文中,研究人员深入分析了莫尔Hubbard模型,该模型被认为能够描述扭曲双层化合物中一个重要亚类的低能物理特性。研究人员构建了涵盖整个磁场范围,直至完全自旋极化状态的磁相图和金属绝缘体相图。研究揭示了模型中丰富的相图,包括完全和部分极化的绝缘相与金属相。此外,研究人员还确定了磁序、塞曼场以及金属丰度之间的相互作用,并将其与近期实验进行了关联。
据悉,在原位控制扭曲双层过渡金属二硫族化合物性质的能力,使它们成为研究强关联性和几何阻挫相互作用的理想平台。特别值得注意的是低能量尺度,这使得在实验上获得带宽或关联尺度量级的温度和磁场成为可能。
附:英文原文
Title: Magnetism and metallicity in moiré transition metal dichalcogenides
Author: Tscheppe, Patrick, Zang, Jiawei, Klett, Marcel, Karakuzu, Seher, Celarier, Armelle, Cheng, Zhengqian, Marianetti, Chris A., Maier, Thomas A., Ferrero, Michel, Millis, Andrew J., Schafer, Thomas
Issue&Volume: 2024-1-11
Abstract: The ability to control the properties of twisted bilayer transition metal dichalcogenides in situ makes them an ideal platform for investigating the interplay of strong correlations and geometric frustration. Of particular interest are the low energy scales, which make it possible to experimentally access both temperature and magnetic fields that are of the order of the bandwidth or the correlation scale. In this manuscript, we analyze the moiré Hubbard model, believed to describe the low energy physics of an important subclass of the twisted bilayer compounds. We establish its magnetic and the metal–insulator phase diagram for the full range of magnetic fields up to the fully spin-polarized state. We find a rich phase diagram including fully and partially polarized insulating and metallic phases of which we determine the interplay of magnetic order, Zeeman-field, and metallicity, and make connection to recent experiments.
DOI: 10.1073/pnas.2311486121
Source: https://www.pnas.org/doi/abs/10.1073/pnas.2311486121