6533b7d4fe1ef96bd126325c
RESEARCH PRODUCT
Time-Resolved Coherent Anti-Stokes Raman Scattering of Graphene: Dephasing Dynamics of Optical Phonon.
Pasi MyllyperkiöJuha KoivistoinenMika Petterssonsubject
PhononDephasingphonons02 engineering and technology01 natural sciencessymbols.namesake0103 physical sciencesscattering (physics)grafeeniGeneral Materials SciencesirontaCoherent anti-Stokes Raman spectroscopyPhysical and Theoretical ChemistryExponential decay010306 general physicsta116fononitPhysicsta114graphene021001 nanoscience & nanotechnologyVibronic couplingsymbolsAtomic physics0210 nano-technologyRaman spectroscopyExcitationRaman scatteringdescription
We report dynamics of the G-mode in graphene probed with time-resolved coherent anti-Stokes Raman scattering measurements. By applying BOXCARS excitation geometry with three different excitation wavelengths, various nonlinear processes can be selectively detected due to energy and momentum conservation and temporal sequence of the pulses. The Raman signal due to resonant coherent excitation of the G-mode shows exponential decay with lifetime of ∼325 ± 50 fs. This decay time is shorter than expected based on the line width of the G-mode in the Raman spectrum. We propose that the unexpectedly short dephasing time is a result of dynamic variation of nonadiabatic coupling of the photoexcited electron distribution and the G-mode.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2017-08-16 | The journal of physical chemistry letters |