Intrinsic donor-bound excitons in ultraclean monolayer semiconductors
Abstract
The monolayer transition metal dichalcogenides are an emergent semiconductor platform exhibiting rich excitonic physics with coupled spin-valley degree of freedom and optical addressability. Here, we report a new series of low energy excitonic emission lines in the photoluminescence spectrum of ultraclean monolayer WSe2. These excitonic satellites are composed of three major peaks with energy separations matching known phonons, and appear only with electron doping. They possess homogenous spatial and spectral distribution, strong power saturation, and anomalously long population (>6 µs) and polarization lifetimes (>100 ns). Resonant excitation of the free inter- and intravalley bright trions leads to opposite optical orientation of the satellites, while excitation of the free dark trion resonance suppresses the satellitesʼ photoluminescence. Defect-controlled crystal synthesis and scanning tunneling microscopy measurements provide corroboration that these features are dark excitons bound to dilute donors, along with associated phonon replicas. Our work opens opportunities to engineer homogenous single emitters and explore collective quantum optical phenomena using intrinsic donor-bound excitons in ultraclean 2D semiconductors.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Feb 08, 2021
- Source ID
- 10.1038/s41467-021-21158-8
Entities
People
- Abhay Pasupathy
- Bumho Kim
- Carmen Rubio-Verdú
- Daniel Rhodes
- David G. Mandrus
- Dirk Englund
- Hanan Dery
- Hongyi Yu
- Hyowon Moon
- James C. Hone
- Jiaqiang Yan
- Kenji Watanabe
- Lukas Mennel
- Minhao He
- Pasqual Rivera
- Song Liu
- Takashi Taniguchi
- Wang Yao
- Xiaodong Xu
Organizations
- Army Research Office
- Office of Emerging Frontiers and Multidisciplinary Activities