I-band-like non-dispersive inter-shell interaction induced Raman lines   in the D band region of double-walled carbon nanotubes
  Non-dispersive, inter-layer interaction induced Raman peaks (I bands) -- in the region of the D band -- have been observed recently for bilayer graphene, when the two layers were rotated with respect to each other. Here, similar observations for double-walled carbon nanotubes (DWCNTs) are theoretically predicted. The prediction is based on double resonance theory, involving non-zone-centered phonons, and the effect of disorder is replaced by interaction between the two tubes. 
B\'alint Gyimesi, J\'anos Koltai, Viktor Z\'olyomi and Jen\H{o}   K\"urti
cond-mat.mes-hall