  Graphene plasmons are able to become the fundermental of novel conceptual
photonic devices, resulting from their unique characteristics containing
excitation at room temperature and tunable spectral selectivity in different
frequencies. The pursuit of efficiently exciting and manipulating graphene
plasmons is necessary and significant for high-performance devices. Here, we
investigate graphene plasmon wave propagating in ferroelectric nanocavity
array. We experimentally show that the the periodic ferroelectric polarizations
could be used for doping graphene into desired spatial carrier density
patterns. Based on a theoretical model that considers periodic ununiform
conductivity across graphene sheet, the simulation results show surface plasmon
polaritons (SPP) in graphene can be excited by an incident light in a similar
way to the excitation of photonic crystal resonant modes. The graphene SPP
resonance can be tuned from ~720 to ~1 000 cm-1 by rescaling the ferroelectric
nanocavity array, and from ~540 to ~780 cm-1 by dynamically changing the
applied gate voltage. Our strategy of graphene carrier engineering to excite
SPP offers a promissing way for large-scale, non-destructive fabrication of
novel graphene photonic devices.
