Dark and bright exciton formation, thermalization, and photoluminescence in monolayer transition metal dichalcogenides

Content Provider	Semantic Scholar
Author	Selig, Malte Berghauser, Gunnar Richter, Marten Bratschitsch, Rudolf Knorr, Andreas Malic, Ermin
Copyright Year	2017
Abstract	The remarkably strong Coulomb interaction in atomically thin transition metal dichalcogenides (TMDs) results in an extraordinarily rich many-particle physics including the formation of tightly bound excitons. Besides optically accessible bright excitonic states, these materials also exhibit a variety of dark excitons. Since they can even lie below the bright states, they have a strong influence on the exciton dynamics, lifetimes, and photoluminescence. While very recently, the presence of dark excitonic states has been experimentally demonstrated, the origin of these states, their formation, and dynamics have not been revealed yet. Here, we present a microscopic study shedding light on time- and energy-resolved formation and thermalization of bright and dark intra- and intervalley excitons as well as their impact on the photoluminescence in different TMD materials. We demonstrate that intervalley dark excitons, so far widely overlooked in current literature, play a crucial role in tungsten-based TMDs giving rise to an enhanced photoluminescence and reduced exciton lifetimes at elevated temperatures.
Starting Page	035017
Ending Page	035017
Page Count	1
File Format	PDF HTM / HTML
DOI	10.1088/2053-1583/aabea3
Volume Number	5
Alternate Webpage(s)	https://arxiv.org/pdf/1703.03317v1.pdf
Alternate Webpage(s)	http://arxiv-export-lb.library.cornell.edu/pdf/1703.03317
Alternate Webpage(s)	https://doi.org/10.1088/2053-1583%2Faabea3
Language	English
Access Restriction	Open
Content Type	Text
Resource Type	Article