Figure 4.
Equivalent doping and enhanced tunability of DLG. (a) Comparison between the experimental extinction spectra of 1L- and 2L-GNRAs with W=33 nm and specific pairs of bias voltage Vg. (b) Band diagram representation of a multilayer graphene stack composed of two layers that are electrically interconnected. The black/red planes represent the Fermi level before/after biasing. (c) Band diagram representation for initially undoped graphene layers being biased. The Fermi levels and carrier densities are represented for SLG (1L), DLG (2L) and its two individual layers (1) and (2). (d) Simulated extinction spectra of the 1L-GNRA with W=33 nm, graphene relaxation time τ=15 fs and varying Fermi level EF. (e) Equivalent carrier density and Fermi level of the 1L- and 2L-GNRA extracted from experimental spectra. The dashed and solid curves represent a linear fit of the equivalent carrier density for the 1L- and 2L-GNRA, respectively.