Please use this identifier to cite or link to this item:
|Title:||Ultrafast electron-optical phonon scattering and quasiparticle lifetime in CVD-grown graphene|
|Citation:||Shang, J., Yu, T., Lin, J., Gurzadyan, G.G. (2011-04-26). Ultrafast electron-optical phonon scattering and quasiparticle lifetime in CVD-grown graphene. ACS Nano 5 (4) : 3278-3283. ScholarBank@NUS Repository. https://doi.org/10.1021/nn200419z|
|Abstract:||Ultrafast quasiparticle dynamics in graphene grown by chemical vapor deposition (CVD) has been studied by UV pump/white-light probe spectroscopy. Transient differential transmission spectra of monolayer graphene are observed in the visible probe range (400-650 nm). Kinetics of the quasiparticle (i.e., low-energy single-particle excitation with renormalized energy due to electron-electron Coulomb, electron-optical phonon (e-op), and optical phonon-acoustic phonon (op-ap) interactions) was monitored with 50 fs resolution. Extending the probe range to near-infrared, we find the evolution of quasiparticle relaxation channels from monoexponential e-op scattering to double exponential decay due to e-op and op-ap scattering. Moreover, quasiparticle lifetimes of mono- and randomly stacked graphene films are obtained for the probe photon energies continuously from 1.9 to 2.3 eV. Dependence of quasiparticle decay rate on the probe energy is linear for 10-layer stacked graphene films. This is due to the dominant e-op intervalley scattering and the linear density of states in the probed electronic band. A dimensionless coupling constant W is derived, which characterizes the scattering strength of quasiparticles by lattice points in graphene. © 2011 American Chemical Society.|
|Source Title:||ACS Nano|
|Appears in Collections:||Staff Publications|
Show full item record
Files in This Item:
There are no files associated with this item.
checked on Mar 17, 2019
WEB OF SCIENCETM
checked on Mar 6, 2019
checked on Dec 28, 2018
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.