  In this article, a few-layered graphene-dielectric multilayer (metamaterial)
electro-optic modulator has been proposed in the mid and far infrared range
that works on electro-absorption mechanism. Graphene, both mono layer and few
layer, is an actively tunable optical material that allows control of
inter-band and intra-band transition by tuning its chemical potential.
Utilizing this unique feature of graphene, we propose a multilayer graphene
dielectric stack where few layer graphene is preferred over mono layer
graphene. Although the total thickness of the stack still remains in the
nanometer range, this device can exhibit superior performances in terms of (i)
high modulation depth, (ii) ultra-broadband performance, (iii) ultra-low
insertion loss due to inherent metamaterial properties, (iv) nanoscale
footprint, (v) polarization independence and (vi) capability of being
integrated to a silicon waveguide. Interestingly, these superior performances,
achievable by using few layer graphene with carefully designed metamaterial,
may not be possible with mono layer graphene. Our proposals have been validated
by both the effective medium theory and general transfer matrix method.
