Fig. 1. (a) Schematic of the SOG capacitor waveguide. (b) Top view (not to scale) of the proposed device. Gray shapes are silicon waveguides, dark gray is the highly p-doped silicon slab, green is graphene, and yellow marks the contacts.

Fig. 2. Optical micrograph picture of the device. Inset shows a detail of the MRR.

Fig. 3. Absorption and effective index of the SOG loaded waveguide at 1.55 μm versus the graphene Fermi level. Blue and red curves are for τ=300 and 30  fs, respectively.

Fig. 4. Simulated transmission at the through (solid lines) and drop (dashed lines) ports of the MRR for different graphene scattering times: (a) τ=30 and (b) 300  fs. Different colors refer to different values of the Fermi level of graphene: black is for μ=0.3  eV, red for μ=0.4  eV, and blue for μ=0.5  eV.

Fig. 5. Computed graphene Fermi level as a function of the V–VDirac voltage.

Fig. 6. Experimental through (solid lines) and drop (dashed lines) transmission spectra for different VGS values. Black curves for VGS=14  V (switch disabled), red curves for VGS=0  V (switch is enabling), and blue curves for VGS=14  V (switch enabled).