课题组博士后郑海红同学在国际纳米权威期刊Nano Research上发表论文

课题组博士后郑海红同学在国际纳米权威期刊Nano Research上发表论文

       近日，课题组博士后郑海红同学在刘老师的指导下，以第一作者在国际纳米权威期刊《纳米研究》(Nano Research，影响因子10.269)上发表题为“Evidence for Interlayer Coupling and Moiré excitons in Twisted WS₂/WS₂ Homostructure Superlattices”(扭角WS₂/WS₂同质结的层间耦合作用和莫尔激子的特性)的实验论文。

图：扭角WS₂/WS₂同质结的层间耦合作用和莫尔激子的特性

       扭曲的范德华(vdW)同质结中的莫尔超晶格为设计二维 (2D) 材料的电子能带结构提供了一个多功能调控平台。在石墨烯和过渡金属二硫属化物(TMDc)莫尔体系中，已经证明扭曲角是调节莫尔超晶格的关键参数。然而，扭曲角大小对莫尔势和层间耦合的影响尚未开展相关的研究和调查。本文中，我们报告了对具有各种扭转角(1.1°、3.3° 和 21°)WS₂/WS₂同质结中层内激子的莫尔势调制的观察。我们将莫尔层内激子归因于由扭曲的WS₂/WS₂同质结构产生的周期性莫尔势的捕获。通过精确调整同质结构的扭转角，可以实现调节莫尔势的深度，捕获更多的激子态。同时，我们通过低频拉曼光谱检测，进一步验证了原子重构在大规模上绘制莫尔晶格中的不均匀性，这赋予了层间耦合的均匀性。我们的研究结果为深入理解扭曲范德华同质结中莫尔激子的光学行为提供了见解，并促进了电子工程和拓扑声子学的研究。

论文链接：

Comments:

• The recent discovery of interlayer coupling and moiré excitons in twisted WS₂/WS₂ homostructure superlattices is a major breakthrough in the field of two-dimensional materials. This is because these phenomena have the potential to greatly enhance the performance of electronic and optoelectronic devices made from these materials.

• The interlayer coupling observed in these superlattices is a result of the interaction between the electronic states in the two layers, which are brought into close proximity by the twist angle between the layers. This interaction leads to the formation of new electronic states with properties that are different from those of the individual layers. These states can be used to create new types of devices with improved performance.

• Moiré excitons, on the other hand, are a result of the interference between the electronic states of the two layers. This interference can lead to the formation of new excitons with unique properties, such as enhanced binding energies and improved radiative decay rates. These excitons can be used to create more efficient optoelectronic devices, such as LEDs and photovoltaic cells.

• Overall, the discovery of interlayer coupling and moiré excitons in twisted WS₂/WS₂ homostructure superlattices is a major step forward in the development of new materials for electronic and optoelectronic applications. The ability to control these phenomena through the manipulation of the twist angle will allow researchers to further explore the potential of these materials in a variety of applications.