Exciton Dipole Orientation of Strain-Induced Quantum Emitters in WSe 2

作者：Yue Luo, Na Liu, Bumho Kim, James Hone, Stefan Strauf · 发表于：Nano Letters · 年份：2020 · DOI：10.1021/acs.nanolett.0c01358 · 被引用次数：40 · 研究领域：2D Materials and Applications、Graphene research and applications、Perovskite Materials and Applications

Transition metal dichalcogenides are promising semiconductors to enable advances in photonics and electronics and have also been considered as a host for quantum emitters. Particularly, recent advances demonstrate site-controlled quantum emitters in WSe 2 through strain deformation. Albeit essential for device integration, the dipole orientation of these strain-induced quantum emitters remains unknown. Here we employ angular-resolved spectroscopy to experimentally determine the dipole orientation of strain-induced quantum emitters. It is found that with increasing local strain the quantum emitters in WSe 2 undergo a transition from in-plane to out-of-plane dipole orientation if their emission wavelength is longer than 750 nm. In addition, the exciton g -factor remains with average values of g = 8.52 ± 1.2 unchanged in the entire emission wavelength. These findings provide experimental support of the interlayer defect exciton model and highlight the importance of an underlying three-dimensional strain profile of deformed monolayer semiconductors, which is essential to optimize emitter-mode coupling in nanoplasmonics.