Fig. 3
From: Broadband impedance match to two-dimensional materials in the terahertz domain
Broadband impedance matching. a Optical photograph of graphene transferred onto ODTS modified oxide on high-resistivity silicon substrate. The scale bar is ~ 5 mm. b Source-drain current vs. gate voltage for typical graphene on ODTS SAM device. The charge neutral point is ~ 22 V. c Transmittance vs. frequency data acquired for a control sample (bare high-resistivity silicon substrate with no graphene). d, e Transmittance vs. frequency data for a graphene sample gated at 20 V and −7 V. f–h Transmittance vs. frequency for three devices after chemical doping to modify the zero-bias sheet resistance. The expected transmittance values assuming the DC conductance as the AC contribution (assuming negligible susceptance) are plotted as dotted lines
