  We analyse a model describing hysteretic behaviour of the reflectivity R for
the system 'graphene-Pb(ZrxTi1-x)O3 (PZT) ferroelectric substrate-gate' with a
gate voltage variation, which takes into account trapping of electrons into the
graphene-PZT interface states. We demonstrate that the hysteresis in the R
parameter can be observed experimentally for the telecommunication-range
radiation (the wavelength {\lambda} = 1.55 {\mu}m) at low gate voltages and,
moreover, the phenomenon can be used while creating fast bistable systems for
the novel nonvolatile memory devices with on-chip optical interconnection.
