  By using non-equilibrium molecular dynamics simulations(NEMD), the modulation
on temperature dependence of thermal conductivity of graphene phononic crystals
(GPnCs) are investigated. It is found that the temperature dependence of
thermal conductivity of GPnCs follows $T^{-\alpha}$ behavior. The power
exponents ($\alpha$) can be efficiently tuned by changing the characteristic
size of GPnCs. The phonon participation ratio spectra and dispersion relation
reveal that the long-range phonon modes are more affected in GPnCs with larger
size of holes ($L_0$). Our results suggest that constructing GPnCs is an
effective method to manipulate the temperature dependence of thermal
conductivity of graphene, which would be beneficial for developing GPnCs-based
thermal management and signal processing devices.
