Figure 3
From: Hybridization of graphene-gold plasmons for active control of mid-infrared radiation
Characterization of the fabricated metasurface. (a) Scanning electron microscopy of a section of the device. (b) Transfer curve of the field-effect transistor device. (c) Measured transmittance as a function of graphene’s Fermi level, given in eV. (d) Calculated differential extinction. (e) Frequency response characterization of the mid-infrared modulator for sinusoidal gate voltages of 80 V (blue) and 40 V (red) peak-to-peak. The modulation experiment was conducted with an optical bandpass filter at 7.5 μm (top) and 11.5 μm (bottom), with passbands shown as the yellow bands in (c) and (d). Cutoff frequencies (− 3 dB, 50%) in (e) compared to max modulation) are marked with vertical black lines.
