Opto-valleytronic imaging of atomically thin semiconductors
- Ludwig Maximilian Univ., Munchen (Germany)
- Rice Univ., Houston, TX (United States)
- Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Transition metal dichalcogenide semiconductors represent elementary components of layered heterostructures for emergent technologies beyond conventional opto-electronics. In their monolayer form they host electrons with quantized circular motion and associated valley polarization and valley coherence as key elements of opto-valleytronic functionality. Here, we introduce two-dimensional polarimetry as means of direct imaging of the valley pseudospin degree of freedom in monolayer transition metal dichalcogenides. Using MoS2 as a representative material with valley-selective optical transitions, we establish quantitative image analysis for polarimetric maps of extended crystals, and identify valley polarization and valley coherence as sensitive probes of crystalline disorder. Moreover, we find site-dependent thermal and non-thermal regimes of valley-polarized excitons in perpendicular magnetic fields. Finally, we demonstrate the potential of widefield polarimetry for rapid inspection of opto-valleytronic devices based on atomically thin semiconductors and heterostructures.
- Research Organization:
- Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
- Sponsoring Organization:
- USDOE
- Grant/Contract Number:
- AC52-06NA25396
- OSTI ID:
- 1375888
- Report Number(s):
- LA-UR-17-25599; TRN: US1702562
- Journal Information:
- Nature Nanotechnology, Vol. 12, Issue 4; ISSN 1748-3387
- Publisher:
- Nature Publishing GroupCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Web of Science
Similar Records
Trion valley coherence in monolayer semiconductors
Photon-Electron Interactions in Dirac Quantum Materials