▎ 摘　　要

This paper derives exactly the stability condition of the dispersive hybrid implicit-explicit finite-difference time-domain (HIE-FDTD) method used for the simulations of the graphene-based devices. Combining with the Routh-Hurwitz criterion, an analytical closed-form stability expression is obtained. The result shows that the maximum time increment of the dispersive HIE-FDTD method is only associated with two spatial discretizations instead of the smallest one inside the graphene layer. Numerical example validates this stability condition.