Strong polarization dependence of double-resonant Raman intensities in graphene.
Spatially resolved and polarized micro-Raman spectroscopy on microcrystalline graphene shows strong polarization dependences of double-resonance Raman intensities. The Raman intensity of the double-resonant 2D band is maximum when the excitation and detection polarizations are parallel and minimum when they are orthogonal, whereas that of the G band is isotropic. A calculation shows that this strong polarization dependence is a direct consequence of inhomogeneous optical absorption and emission mediated by electron-phonon interactions involved in the second-order Stokes-Stokes Raman scattering process.
Department of Physics, Sogang University, Seoul 121-742, Korea.
Duhee
D
Yoon
Hyerim
H
Moon
Young-Woo
YW
Son
Bae Ho
BH
Park
Jin Bae
JB
Kim
Youngpak
Y
Lee
Hyeonsik
H
Cheong