Kohn anomaly and electron-phonon interaction at the K-derived point of the brillouin zone of metallic nanotubes.
We applied Raman spectroscopy to investigate the response to electrochemical doping of the second-order D* band in single-walled carbon nanotube (SWNT) bundles. Our study reveals a dramatic increase of the D* band sensitivity to doping upon moving the laser excitation to the red end of the visible spectrum and beyond. Using the double-resonance scattering model, we show that this phenomenon evidences a second Kohn anomaly in metallic SWNTs, located in the K-point-derived region of the Brillouin zone (BZ), which stems from the Kohn anomaly at the K-point of graphene. Our results will be compared to recent doping experiments on graphene with field-effect gating and can be used to investigate the wave-vector dependent electron-phonon coupling in the bulk of the BZ of metallic SWNTs.
Rafailov
Peter M
PM
Georgi Nadjakov Institute of Solid State Physics, Bulgarian Academy of Sciences, 1784 Sofia, Bulgaria. rafailov@issp.bas.bg
Maultzsch
Janina
J
Thomsen
Christian
C
Dettlaff-Weglikowska
Urszula
U
Roth
Siegmar
S
D003198:Computer Simulation; D004563:Electrochemistry; D004583:Electrons; D006108:Graphite / Q000737:chemistry; D008422:Materials Testing; D053768:Metal Nanoparticles / Q000737:chemistry*; D008956:Models, Chemical; D036103:Nanotechnology / Q000379:methods*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D013059:Spectrum Analysis, Raman
D037742:Nanotubes, Carbon; D006108:Graphite