What Has Been Achieved:
A photoluminescence feature has been identified as excitons bound to charged sulfur vacancies in 2D WS2.
Importance of Achievement
The study identifies a fast, inexpensive, and non-destructive characterization method to assess the quality of 2D transition metal dichalcogenide crystals.
Unique Features of the MIP That Enabled Project:
Close collaboration between synthesis, characterization, and theory efforts.
V. Carozo, Y. Wang, K. Fujisawa, B. R. Carvalho, A. McCreary, S. Feng, Z. Lin, C. Zhou, N. Perea-López, A. L. Elías, B. Kabius, V. H. Crespi, and M. Terrones, “Optical identification of sulfur vacancies: Bound excitons at the edges of monolayer tungsten disulfide”, Sci. Adv. 3, e1602813 (2017).
Identifying Defects. An atomically thin WS2 flake is shown to be excited by a laser and emit light at a different wavelength at the three edges of the triangular flake. The inset illustrates an electron-hole pair being trapped at a sulfur vacancy site.
Credits/Names: Carozo, Wang, Fujisawa, Carvalho, McCreary, Feng, Lin, Zhou, Perea-López, Elías, Kabius, Crespi, Terrones, Penn State, Universidade Federal de Minas Gerais
Download PDF Version: MIP-2DCC-1539916_ExcitonsBoundToDefects_2017.pdf
Year of Research Highlight: 2017
Select a Highlight Type: In-House Research Highlight