@article{b71834b40c334dbba6d8ef00be8ca2f6,
title = "Semiconductor Nanoplatelet Excimers",
abstract = "Excimers, a portmanteau of {"}excited dimer{"}, are transient species that are formed from the electronic interaction of a fluorophore in the excited state with a neighbor in the ground state, which have found extensive use as laser gain media. Although common in molecular fluorophores, this work presents evidence for the formation of excimers in a new class of materials: atomically precise two-dimensional semiconductor nanoplatelets. Colloidal nanoplatelets of CdSe display two-color photoluminescence resolved at low temperatures with one band attributed to band-edge fluorescence and a second, red band attributed to excimer fluorescence. Previously reasonable explanations for two-color fluorescence, such as charging, are shown to be inconsistent with additional evidence. As with excimers in other materials systems, excimer emission is increased by increasing nanoplatelet concentration and the degree of cofacial stacking. Consistent with their promise as low-threshold gain media, amplified spontaneous emission emerges from the excimer emission line.",
keywords = "Excimer, amplified spontaneous emission, nanoplatelet, photoluminescence, two-dimensional",
author = "Diroll, {Benjamin T.} and Wooje Cho and Igor Coropceanu and Harvey, {Samantha M.} and Alexandra Brumberg and Nicholas Holtgrewe and Crooker, {Scott A.} and Wasielewski, {Michael R.} and Prakapenka, {Vitali B.} and Talapin, {Dmitri V.} and Schaller, {Richard D.}",
note = "Funding Information: This work was performed, in part, at the Center for Nanoscale Materials, a U.S. Department of Energy (DOE) Office of Science User Facility under Contract No. DE-AC02-06CH11357. This research used resources of the Advanced Photon Source, DOE Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. Work at the National High Magnetic Field Laboratory was supported by NSF DMR-1644779 and the State of Florida. A.B. and S.M.H. acknowledge support by the National Science Foundation (NSF) Research Fellowship Program under Grant DGE-1324585. The authors acknowledge support from the NSF DMREF Program under awards DMR-1629601 and DMR-1629383 and from the Department of Defense Air Force Office of Scientific Research under Grant FA9550-15-1-0099 (D.V.T). This research was also supported by the National Science Foundation under Grant DMR-1710104 (M.R.W.). GeoSoilEnviroCARS is supported by NSF Earth Sciences Grant EAR-1634415 and the DOE, Geosciences under Grant DE-FG02-94ER14466. The use of optical integrated system at GSECARS is supported by NSF-MRI Grant EAR-1531583. Publisher Copyright: {\textcopyright} 2018 American Chemical Society.",
year = "2018",
month = nov,
day = "14",
doi = "10.1021/acs.nanolett.8b02865",
language = "English (US)",
volume = "18",
pages = "6948--6953",
journal = "Nano Letters",
issn = "1530-6984",
publisher = "American Chemical Society",
number = "11",
}