Voltage-controlled surface plasmon-polaritons in double graphene layer   structures
  We study the spectra and damping of surface plasmon-polaritons in double graphene layer structures. It is shown that application of bias voltage between layers shifts the edge of plasmon absorption associated with the interband transitions. This effect could be used in efficient plasmonic modulators. We reveal the influence of spatial dispersion of conductivity on plasmonic spectra and show that it results in the shift of cutoff frequency to the higher values. 
D. Svintsov, V. Vyurkov, V. Ryzhii, and T. Otsuji
cond-mat.mes-hall physics.plasm-ph