Extracting the complex optical conductivity of mono- and bilayer graphene by ellipsometry

  title={Extracting the complex optical conductivity of mono- and bilayer graphene by ellipsometry},
  author={You-Chia Chang and Chang-Hua Liu and Che-Hung Liu and Zhaohui Zhong and Theodore B. Norris},
  journal={Applied Physics Letters},
A method for analysis of spectroscopic ellipsometry data is demonstrated to extract the optical conductivity of mono- and bilayer chemical-vapor-deposited graphene. We model graphene as a truly two-dimensional (2D) material with a sheet conductivity, rather than a phenomenological effective refractive index as has been used in the literature. This technique measures both the real and imaginary part of the optical conductivity, which is important for graphene optoelectronics and metamaterials… 

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