Yoon Duhee, Moon Hyerim, Son Young-Woo, Park Bae Ho, Kim Jin Bae, Lee Youngpak, Cheong Hyeonsik
Department of Physics, Sogang University, Seoul 121-742, Korea.
Nano Lett. 2008 Dec;8(12):4270-4. doi: 10.1021/nl8017498.
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.
对微晶石墨烯进行空间分辨和偏振微拉曼光谱研究，结果表明双共振拉曼强度具有很强的偏振依赖性。当激发偏振和探测偏振平行时，双共振2D带的拉曼强度最大，而当它们正交时则最小，而G带的拉曼强度是各向同性的。计算表明，这种强烈的偏振依赖性是二阶斯托克斯-斯托克斯拉曼散射过程中涉及的电子-声子相互作用介导的非均匀光吸收和发射的直接结果。
