Four-fold Raman enhancement of 2D band in twisted bilayer graphene: evidence for a doubly degenerate Dirac band and quantum interference.

@article{Wang2014FourfoldRE,
  title={Four-fold Raman enhancement of 2D band in twisted bilayer graphene: evidence for a doubly degenerate Dirac band and quantum interference.},
  author={Yanan Wang and Zhihua Su and Wei Chen Wu and Shu Nie and Xinghua Lu and Haiyan Wang and Kevin McCarty and Shin-shem Pei and Francisco Robles-Hernandez and Viktor G. Hadjiev and Jiming Bao},
  journal={Nanotechnology},
  year={2014},
  volume={25 33},
  pages={335201}
}
We report the observation of a strong 2D band Raman in twisted bilayer graphene (tBLG) with large rotation angles under 638 nm and 532 nm visible laser excitations. The 2D band Raman intensity increased four-fold as opposed to the two-fold increase observed in single-layer graphene. The same tBLG samples also exhibited rotation-dependent G-line resonances… CONTINUE READING