Single-photon emission from localized excitons in an atomically thin semiconductor
- 1 April 2015
- journal article
- Published by Optica Publishing Group in Optica
- Vol. 2 (4), 347-352
- https://doi.org/10.1364/optica.2.000347
Abstract
Single-photon sources are basic building blocks for quantum communications, processing, and metrology. Solid-state quantum emitters in semiconductors have the potential for robust and reliable generation of photons, and atomically thin transition metal dichalcogenides, such as MoS2, MoSe2, WS2, and WSe2, are a promising new class of two-dimensional semiconductors with a direct optical bandgap in the visible or near-IR. Here, we observe bright and stable single-photon emission from localized excitons in a monolayer of tungsten diselenide (WSe2). The emitters appear at the edges of the flakes and are linearly polarized. The spectral width of their emission is below 120 μeV in a freestanding WSe2 monolayer. Photoluminescence excitation spectroscopy reveals the excitonic nature of the emitters and provides evidence that these single excitons originate from free excitons trapped in local potential wells at the edges of the atomically thin flakes. We find that the emitters can also be deterministically created by scratching the WSe2 monolayer. Their excellent spectral stability implies that these localized single-photon emitters could find application in optoelectronics. Our results light the way to single exciton physics and quantum optics with atomically thin semiconductors.Keywords
This publication has 29 references indexed in Scilit:
- Two-dimensional material nanophotonicsNature Photonics, 2014
- Monolayer diodes light upNature Nanotechnology, 2014
- Van der Waals heterostructuresNature, 2013
- Photoluminescence emission and Raman response of monolayer MoS_2, MoSe_2, and WSe_2Optics Express, 2013
- Electronics and optoelectronics of two-dimensional transition metal dichalcogenidesNature Nanotechnology, 2012
- Polarized light boosts valleytronicsNature Nanotechnology, 2012
- Low-temperature photocarrier dynamics in monolayer MoS2Applied Physics Letters, 2011
- Atomically Thin: A New Direct-Gap SemiconductorPhysical Review Letters, 2010
- Emerging Photoluminescence in Monolayer MoS2Nano Letters, 2010
- Physical properties of layer structures : optical properties and photoconductivity of thin crystals of molybdenum disulphideProceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences, 1963