Ultrafast Graphene Light Emitters
Name
1710.08599.pdf
Description
Accepted version
Size
3.69 MB
Format
Adobe PDF
Checksum (MD5)
b4d56166ad4dab4e1748d2a2a43eab6f
Author(s)
Kim, Young Duck
Gao, Yuanda
Shiue, Ren-Jye
Wang, Lei
Aslan, Ozgur
Bae, Myung-Ho
Kim, Hyungsik
Seo, Dongjea
Choi, Heon-Jin
Kim, Suk Hyun
Date Issued
January 22, 2018
Journal
Nano Letters
Publisher
American Chemical Society
Citation
Young Duck Kim et al. "Ultrafast Graphene Light Emitters." Nano Letters 18, 2 (January 2018): 934-940 © 2018 American Chemical Society
Version
Author's final manuscript
Abstract
Ultrafast electrically driven nanoscale light sources are critical components in nanophotonics. Compound semiconductor-based light sources for the nanophotonic platforms have been extensively investigated over the past decades. However, monolithic ultrafast light sources with a small footprint remain a challenge. Here, we demonstrate electrically driven ultrafast graphene light emitters that achieve light pulse generation with up to 10 GHz bandwidth across a broad spectral range from the visible to the near-infrared. The fast response results from ultrafast charge-carrier dynamics in graphene and weak electron-acoustic phonon-mediated coupling between the electronic and lattice degrees of freedom. We also find that encapsulating graphene with hexagonal boron nitride (hBN) layers strongly modifies the emission spectrum by changing the local optical density of states, thus providing up to 460% enhancement compared to the gray-body thermal radiation for a broad peak centered at 720 nm. Furthermore, the hBN encapsulation layers permit stable and bright visible thermal radiation with electronic temperatures up to 2000 K under ambient conditions as well as efficient ultrafast electronic cooling via near-field coupling to hybrid polaritonic modes under electrical excitation. These high-speed graphene light emitters provide a promising path for on-chip light sources for optical communications and other optoelectronic applications. Keywords: graphene; ultrafast light emitter; thermal radiation; van der Waals heterostructure; optoelectronics
Subjects
Mechanical Engineering
General Materials Science
Bioengineering
General Chemistry
Condensed Matter Physics
MIT Department
Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science
Terms of Use
Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1021/acs.nanolett.7b04324
