  Using the Gaussian R\'enyi-2 entropy, we analyse the behaviour of two
different aspects of quantum correlations (entanglement and quantum discord) in
two optomechanical subsystems (optical and mechanical). We work in the resolved
sideband and weak coupling regimes. In experimentally accessible parameters, we
show that it is possible to create entanglement and quantum discord in the
considered subsystems by quantum fluctuations transfer from either light to
light or light to matter. We find that both mechanical and optical entanglement
are strongly sensitive to thermal noises. In particular, we find that the
mechanical one is more affected by thermal effects than that optical. Finally,
we reveal that under thermal noises, the discord associated with the entangled
state decays aggressively, whereas the discord of the separable state
(quantumness of correlations) exhibits a freezing behaviour, seeming to be
captured over a wide range of temperature.
