论文标题
在扭曲过渡金属二甲基元素异质结构中的层中激子的Moiré-Bose-Hubbard模型
Moiré-Bose-Hubbard model for interlayer excitons in twisted transition metal dichalcogenide heterostructures
论文作者
论文摘要
在半导体过渡金属二核苷的双层中，可以使用层之间的扭曲角来引入高度规则的周期性电势调制，该长度比单元相比大。在这样的结构中，相关状态可以出现，其中异质结构中的激子由于激子 - 外激体相互作用而强烈地定位于潜在的最小值。我们探讨了莫特（Mott）和延长激子阶段之间的过渡，从莫伊尔·霍斯（Moiré-Bose）哈伯顿式汉密尔顿（Hamiltonian）角度来看。跳和现场相互作用参数是从层间脱落 - 外部波函数的Wannier表示获得的，并使用非本地Rytova-keldysh模型来归因于二维材料中激子的介电筛选。对于足够小的激子浓度和底物筛选，我们的模型可以预测莫特胰岛状态的出现，从而建立扭曲的TMD异质结构作为玻色粒多体系统的可能量子模拟器。
In bilayers of semiconducting transition metal dichalcogenides, the twist angle between layers can be used to introduce a highly regular periodic potential modulation on a length scale that is large compared to the unit cell. In such structures, correlated states can emerge, in which excitons in the heterostructure are strongly localized to the potential minima due to exciton-exciton interactions. We explore the transition between Mott and extended exciton phases in terms of a moiré-Bose-Hubbard Hamiltonian. Hopping and on-site interaction parameters are obtained from a Wannier representation of the interlayer-exciton wave functions, and a non-local Rytova-Keldysh model is used to attribute for the dielectric screening of excitons in the two-dimensional material. For sufficiently small exciton concentrations and substrate screening our model predicts the emergence of Mott-insulating states, establishing twisted TMD heterostructures as possible quantum simulators for bosonic many-body systems.
