Maultzsch J, Reich S, Schlecht U, Thomsen C
Institut für Festkörperphysik, Technische Universität Berlin, Hardenbergstrasse 36, 10623 Berlin, Germany.
Phys Rev Lett. 2003 Aug 22;91(8):087402. doi: 10.1103/PhysRevLett.91.087402. Epub 2003 Aug 19.
We present excitation-energy dependent Raman measurements between 2.05 and 2.41 eV on the same individual carbon nanotube. We find a change in the Raman frequencies of both the D mode (63 cm(-1)/eV) and the high-energy modes. The observed frequencies of the modes at approximately 1600 cm(-1) as a function of laser-energy map the phonon dispersion relation of a metallic tube near the Gamma point of the Brillouin zone. Our results prove the entire first-order Raman spectrum in single-wall carbon nanotubes to originate from double-resonant scattering. Moreover, we confirm experimentally the phonon softening in metallic tubes by a Peierls-like mechanism.
我们展示了在同一根单独的碳纳米管上进行的2.05至2.41电子伏特之间的激发能量相关拉曼测量。我们发现D模式（63厘米⁻¹/电子伏特）和高能模式的拉曼频率都发生了变化。在大约1600厘米⁻¹处观察到的模式频率作为激光能量的函数，描绘了布里渊区伽马点附近金属管的声子色散关系。我们的结果证明单壁碳纳米管中的整个一阶拉曼光谱源于双共振散射。此外，我们通过类似派尔斯的机制在实验上证实了金属管中的声子软化。
