Nano-optical imaging of waveguide modes revealing light-exciton interactions
- Argonne National Lab. (ANL), Lemont, IL (United States); Iowa State Univ., Ames, IA (United States)
- Univ. of Washington, Seattle, WA (United States)
- Argonne National Lab. (ANL), Lemont, IL (United States)
- Argonne National Lab. (ANL), Lemont, IL (United States); William Paterson Univ., Wayne, NJ (United States)
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States)
- Fudan Univ., Shanghai (China)
We report on a nano-optical imaging study of WSe2 thin flakes with scanning near-field optical microscopy (NSOM). The NSOM technique allows us to visualize in real space various waveguide photon modes inside WSe2. By tuning the excitation laser energy, we are able to map the entire dispersion of these waveguide modes both above and below the A exciton energy of WSe2. We found that all the modes interact strongly with WSe2 excitons. The outcome of the interaction is that the observed waveguide modes shift to higher momenta right below the A exciton energy. At higher energies, on the other hand, these modes are strongly damped due to adjacent B excitons or band-edge absorptions. Furthermore, the mode-shifting phenomena are consistent with polariton formation in WSe2.
- Research Organization:
- Argonne National Lab. (ANL), Argonne, IL (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC), Basic Energy Sciences (BES)
- Grant/Contract Number:
- AC02-06CH11357; AC05-00OR22725
- OSTI ID:
- 1369571
- Alternate ID(s):
- OSTI ID: 1280187; OSTI ID: 1376353
- Journal Information:
- Physical Review B, Vol. 94, Issue 8; ISSN 2469-9950
- Publisher:
- American Physical Society (APS)Copyright Statement
- Country of Publication:
- United States
- Language:
- English
Web of Science
Similar Records
Electrical Tuning of Exciton Binding Energies in Monolayer
Spatial extent of the excited exciton states in monolayers from diamagnetic shifts