Lineshape characterization of excitons in monolayer WS2 by two-dimensional electronic spectroscopy
- University of California, Berkeley, CA (United States); Kavli Energy NanoScience Institute, Berkeley, CA (United States); Southern University of Science and Technology (SUSTech), Shenzhen (China)
- National Tsing-Hua University, Hsinchu (Taiwan)
- Wuhan University (China)
- University of California, Berkeley, CA (United States); Kavli Energy NanoScience Institute, Berkeley, CA (United States)
- University of California, Berkeley, CA (United States); Kavli Energy NanoScience Institute, Berkeley, CA (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
The optical properties of monolayer transition metal dichalcogenides (TMDCs), an important family of two-dimensional (2D) semiconductors for optoelectronic applications, are dominated by two excitons A (XA) and B (XB) located at K/K's valleys. The lineshape of the excitons is an indicator of the interaction of the excitons with other particles and also largely determines the performance of TMDC-based optoelectronic devices. In this work, we apply 2D electronic spectroscopy (2DES), which enables separation of the intrinsic homogeneous linewidth and the extrinsic inhomogeneous linewidth, to dissect the lineshape of XA in monolayer WS2. With a home-built broadband optical parametric amplifier, the 2D spectra give the exciton linewidth values for extensive ranges of excitation densities and temperatures, reflecting inter-exciton and exciton–phonon interactions. Meanwhile, the time-domain evolution of the lineshape reveals a similar rate of spectral diffusion to that in quantum wells (QWs) based on III–V semiconductors.
- Research Organization:
- Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
- Sponsoring Organization:
- USDOE; National Science Foundation (NSF); Ministry of Science and Technology (MOST)
- Grant/Contract Number:
- AC02-05CH11231
- OSTI ID:
- 2470943
- Journal Information:
- Nanoscale Advances, Journal Name: Nanoscale Advances Journal Issue: 6 Vol. 2; ISSN 2516-0230
- Publisher:
- Royal Society of ChemistryCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Similar Records
Exchange-driven intravalley mixing of excitons in monolayer transition metal dichalcogenides
Nonlinear optical selection rule based on valley-exciton locking in monolayer ws2