skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Intrinsic homogeneous linewidth and broadening mechanisms of excitons in monolayer transition metal dichalcogenides

Abstract

In this paper, the band-edge optical response of transition metal dichalcogenides, an emerging class of atomically thin semiconductors, is dominated by tightly bound excitons localized at the corners of the Brillouin zone (valley excitons). A fundamental yet unknown property of valley excitons in these materials is the intrinsic homogeneous linewidth, which reflects irreversible quantum dissipation arising from system (exciton) and bath (vacuum and other quasiparticles) interactions and determines the timescale during which excitons can be coherently manipulated. Here we use optical two-dimensional Fourier transform spectroscopy to measure the exciton homogeneous linewidth in monolayer tungsten diselenide (WSe 2). The homogeneous linewidth is found to be nearly two orders of magnitude narrower than the inhomogeneous width at low temperatures. We evaluate quantitatively the role of exciton–exciton and exciton–phonon interactions and population relaxation as linewidth broadening mechanisms. The key insights reported here—strong many-body effects and intrinsically rapid radiative recombination—are expected to be ubiquitous in atomically thin semiconductors.

Authors:
 [1];  [2];  [3];  [4];  [2];  [2];  [2];  [5];  [5];  [6];  [7];  [6];  [2]
  1. Univ. of Texas at Austin, Austin, TX (United States); National Institute of Standards & Technology, Boulder, CO (United States)
  2. Univ. of Texas at Austin, Austin, TX (United States)
  3. Feng Chia Univ., Taichung (Taiwan)
  4. King Abdullah Univ. of Science & Technology (KAUST), Thuwal (Saudi Arabia)
  5. Univ. of Washington, Seattle, WA (United States)
  6. Technische Univ. Berlin, Berlin (Germany)
  7. Chalmers Univ. of Technology, Gothenburg (Sweden)
Publication Date:
Research Org.:
Univ. of Washington, Seattle, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1441157
Grant/Contract Number:  
SC0008145
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Nature Communications
Additional Journal Information:
Journal Volume: 6; Journal Issue: 1; Journal ID: ISSN 2041-1723
Publisher:
Nature Publishing Group
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE

Citation Formats

Moody, Galan, Dass, Chandriker Kavir, Hao, Kai, Chen, Chang -Hsiao, Li, Lain -Jong, Singh, Akshay, Tran, Kha, Clark, Genevieve, Xu, Xiaodong, Berghauser, Gunnar, Malic, Ermin, Knorr, Andreas, and Li, Xiaoqin. Intrinsic homogeneous linewidth and broadening mechanisms of excitons in monolayer transition metal dichalcogenides. United States: N. p., 2015. Web. doi:10.1038/ncomms9315.
Moody, Galan, Dass, Chandriker Kavir, Hao, Kai, Chen, Chang -Hsiao, Li, Lain -Jong, Singh, Akshay, Tran, Kha, Clark, Genevieve, Xu, Xiaodong, Berghauser, Gunnar, Malic, Ermin, Knorr, Andreas, & Li, Xiaoqin. Intrinsic homogeneous linewidth and broadening mechanisms of excitons in monolayer transition metal dichalcogenides. United States. doi:10.1038/ncomms9315.
Moody, Galan, Dass, Chandriker Kavir, Hao, Kai, Chen, Chang -Hsiao, Li, Lain -Jong, Singh, Akshay, Tran, Kha, Clark, Genevieve, Xu, Xiaodong, Berghauser, Gunnar, Malic, Ermin, Knorr, Andreas, and Li, Xiaoqin. Fri . "Intrinsic homogeneous linewidth and broadening mechanisms of excitons in monolayer transition metal dichalcogenides". United States. doi:10.1038/ncomms9315. https://www.osti.gov/servlets/purl/1441157.
@article{osti_1441157,
title = {Intrinsic homogeneous linewidth and broadening mechanisms of excitons in monolayer transition metal dichalcogenides},
author = {Moody, Galan and Dass, Chandriker Kavir and Hao, Kai and Chen, Chang -Hsiao and Li, Lain -Jong and Singh, Akshay and Tran, Kha and Clark, Genevieve and Xu, Xiaodong and Berghauser, Gunnar and Malic, Ermin and Knorr, Andreas and Li, Xiaoqin},
abstractNote = {In this paper, the band-edge optical response of transition metal dichalcogenides, an emerging class of atomically thin semiconductors, is dominated by tightly bound excitons localized at the corners of the Brillouin zone (valley excitons). A fundamental yet unknown property of valley excitons in these materials is the intrinsic homogeneous linewidth, which reflects irreversible quantum dissipation arising from system (exciton) and bath (vacuum and other quasiparticles) interactions and determines the timescale during which excitons can be coherently manipulated. Here we use optical two-dimensional Fourier transform spectroscopy to measure the exciton homogeneous linewidth in monolayer tungsten diselenide (WSe2). The homogeneous linewidth is found to be nearly two orders of magnitude narrower than the inhomogeneous width at low temperatures. We evaluate quantitatively the role of exciton–exciton and exciton–phonon interactions and population relaxation as linewidth broadening mechanisms. The key insights reported here—strong many-body effects and intrinsically rapid radiative recombination—are expected to be ubiquitous in atomically thin semiconductors.},
doi = {10.1038/ncomms9315},
journal = {Nature Communications},
number = 1,
volume = 6,
place = {United States},
year = {Fri Sep 18 00:00:00 EDT 2015},
month = {Fri Sep 18 00:00:00 EDT 2015}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 113 works
Citation information provided by
Web of Science

Save / Share:

Works referenced in this record:

Emerging Photoluminescence in Monolayer MoS2
journal, April 2010

  • Splendiani, Andrea; Sun, Liang; Zhang, Yuanbo
  • Nano Letters, Vol. 10, Issue 4, p. 1271-1275
  • DOI: 10.1021/nl903868w

Electronics and optoelectronics of two-dimensional transition metal dichalcogenides
journal, November 2012

  • Wang, Qing Hua; Kalantar-Zadeh, Kourosh; Kis, Andras
  • Nature Nanotechnology, Vol. 7, Issue 11, p. 699-712
  • DOI: 10.1038/nnano.2012.193

Atomically Thin MoS2 A New Direct-Gap Semiconductor
journal, September 2010