arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2009.14224cond-mat.str-elcond-mat.mtrl-sci
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扭转过渡金属双硫族化合物双层膜的电子结构、电荷转移和电荷序

Electronic structures, charge transfer and charge orders in twisted transition metal dichalcogenide bilayers

Yang Zhang, Tongtong Liu, Liang Fu

摘要:

过渡金属二硫属化物(TMD)双层膜的莫尔超晶格中存在相关电子态,这种相关电子态是由莫尔势和长程库仑相互作用共同作用引起的。本文从理论上研究了过渡金属双硫族化物同质双层云纹超晶格的结构弛豫和单粒子电子性质,并研究了MX和XM区有效蜂窝晶格中的基态电荷序。通过大尺度密度泛函理论计算和层自由度连续介质模型,我们发现面外的门控场产生了一个可调的电荷转移带隙,并在Dirac谱中引入了质量项.在平带极限下,我们用蒙特卡罗模拟观察到了不同填充n = 1/4,1/3,1/2,2/3,1时的一系列电荷有序绝缘态,并预言了在固定填充n = 1/2,2/3时,门控场诱导不同电子晶体间的相变.我们的工作表明,过渡金属二硫属化物均质双层膜提供了一个强大的平台,可调的电荷转移绝缘体和电荷秩序的调查。

英文摘要:

Moire superlattices of transition metal dichalcogenide (TMD) bilayers have been shown to host correlated electronic states, which arises from the interplay of emergent moire potential and long-range Coulomb interactions. Here we theoretically investigate structural relaxation and single-particle electronic properties in moire superlattices of transition metal dichalcogenide homobilayer and study the ground state charge orders in the effective honeycomb lattice of MX and XM region. From the large-scale density functional theory calculation and continuum model with layer degrees of freedom, we find that the out of plane gating field creates a tunable charge transfer gap and introduces a mass term in the Dirac spectrum. At the flat band limit, we observe a series of charge-ordered insulating states at various filling n = 1/4, 1/3, 1/2, 2/3, 1 with Monte Carlo simulations, and predict that gating field induces a phase transition between different electron crystals at fixed filling n = 1/2, 2/3. Our work demonstrates that transition metal dichalcogenide homobilayer provides a powerful platform for the investigation of tunable charge transfer insulator and charge orders.

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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