Moire quantum chemistry: Charge transfer in transition metal dichalcogenide superlattices

被引：110

作者：

Zhang, Yang ^{[1
]}

Yuan, Noah F. Q. ^{[1
]}

Fu, Liang ^{[1
]}

机构：

[1] MIT, Dept Phys, Cambridge, MA 02139 USA

来源：

PHYSICAL REVIEW B | 2020年 / 102卷 / 20期

关键词：

Calculations - Electronic structure - Continuum mechanics - Crystal structure - Charge transfer - Mott insulators - Transition metals;

D O I：

10.1103/PhysRevB.102.201115

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Transition metal dichalcogenide (TMD) bilayers have recently emerged as a robust and tunable moire system for studying and designing correlated electron physics. In this Rapid Communication, by combining a large-scale first-principles calculation and continuum model approach, we provide an electronic structure theory that maps long-period TMD heterobilayer superlattices onto diatomic crystals with cations and anions. We find that the interplay between the moire potential and Coulomb interaction leads to filling-dependent charge transfer between different moire superlattice regions. We show that the insulating state at half filling found in recent experiments on WSe2/WS2 is a charge-transfer insulator rather than a Mott-Hubbard insulator. Our work reveals the richness of simplicity in moire quantum chemistry.

引用

页数：6