课题组博士生吴彪同学在国际纳米权威期刊Nanoscale上发表论文

      近日，课题组成员吴彪同学在刘老师的指导下，以第一作者在国际纳米权威期刊Nanoscale (影响因子8.307)上发表题为 “Observation of Moiré Excitons in Twisted WS₂/WS₂ Homostructure Superlattices”(扭角同质结中WS₂/WS₂莫尔激子的特性)的实验论文。

图：扭角同质结中WS₂/WS₂莫尔激子的特性

        莫尔超晶格为设计光学激子的特性提供了一个迷人的平台。莫尔图案可以在空间中产生有序的激子阵列，使拓扑激子和量子发射器成为可能。最近，已广泛报道了 TMD 扭角异质结构中莫尔激子的证据。然而，迄今为止，对扭曲同质结构中的莫尔激子的捕获和研究仍然难以捉摸。本文中，我们报告了在具有小扭转角的 WS₂/WS₂ 同质结构中对莫尔激子的观察。扭曲同质结构区域的PL光谱显示出许多具有几乎恒定峰间距的小峰，这归因于莫尔势作为周期性陷阱用于限制层内激子，从而形成有序的莫尔激子阵列。此外，我们还研究了不同温度和激光功率对莫尔激子的影响，以及莫尔激子的谷极化。我们的研究结果为进一步探索 TMDs 莫尔超晶格的人造激子晶体和量子发射器提供了广阔的前景。

文章链接：https://pubs.rsc.org/en/content/articlepdf/2022/NR/D2NR02450K

Comments:

• The observation of Moiré excitons in twisted WS₂/WS₂ homostructure superlattices refers to the recent discovery of excitonic states in the superlattice structures composed of two single-layer tungsten disulfide (WS₂) crystals with a relative twist angle between them.

• In a Moiré pattern, the periodic modulation of the crystal lattice structure creates new excitonic states with distinct energies and spatial distributions. These excitons, known as Moiré excitons, can exhibit unique optical and electronic properties, such as long lifetimes and strong light-matter interaction.

• The study of Moiré excitons in WS₂/WS₂ superlattices can lead to a deeper understanding of the interplay between lattice geometry and electronic structure and may have potential applications in optoelectronics, such as light-emitting diodes and photovoltaic devices.

• Overall, the observation of Moiré excitons in twisted WS₂/WS₂ superlattices represents an important step forward in the field of two-dimensional materials and their applications.