Single Photon Emission from Deep Level Defects in Monolayer WSe2

Abstract

We report an efficient method to observe single photon emissions in monolayer WSe2 by applying hydrostatic pressure. The photoluminescence peaks of typical two-dimensional (2D) excitons show a nearly identical pressure-induced blue-shift, whereas the energy of pressure-induced discrete emission lines (quantum emitters) demonstrates a pressure insensitive behavior. The decay time of these discrete line emissions is approximately 10 ns, which is at least one order longer than the lifetime of the broad localized (L) excitons. These characteristics lead to a conclusion that the excitons bound to deep level defects can be responsible for the observed single photon emissions.

12 pages, 4 figures

References in corpus (6)

• Strong Photoluminescence Enhancement of MoS2 through Defect Engineering and Oxygen Bonding
• Valley Zeeman Effect in Elementary Optical Excitations of a Monolayer WSe2
• Strain-induced spatial and spectral isolation of quantum emitters in mono- and bi-layer WSe2
• Exciton Valley Dynamics probed by Kerr Rotation in WSe2 Monolayers
• Discrete quantum dot like emitters in monolayer MoSe2: Spatial mapping, Magneto-optics and Charge tuning
• Localized defect states in MoS${}_2$ monolayers: electronic and optical properties

Cited by in corpus (4)

• Strain-induced bound states in transition-metal dichalcogenide bubbles
• Radiative lifetime of localized excitons in transition metal dichalcogenides
• Controlled defect production in monolayer MoS2 via electron irradiation at ultralow accelerating voltages
• High-purity and stable single-photon emission in bilayer WSe${}_2$ via phonon-assisted excitation