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

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…

• NS
  National Science Foundation

  Awards: NSF DMR-1306878, DMR-1306878, 1306878
• GF
  Graphene Flagship

  Awards: CNECT-ICT-604391, 604391
• AO
  Asian Office of Aerospace Research and Development
• EC
  European Commission

  Awards: 604391, CNECT-ICT-604391
• AS
  Academia Sinica
• KA
  King Abdullah University of Science and Technology
• DO
  Division of Materials Research

  Awards: DMR-1306878, 1306878
• AF
  Air Force Office of Scientific Research

  Awards: 134137, FA9550-, AOARD-134137, FA9550-10-1-0022, FA9550