  Dynamically probing systems of ultrastrongly coupled light and matter by
advanced coherent control has been recently proposed as a unique tool for
detecting peculiar quantum features of this regime. Coherence allows in
principle on-demand conversion of virtual photons dressing the entangled
eigenstates of the system to real ones, with unitary efficiency and remarkable
robustness. Here we study this effect in the presence of decoherence, showing
that also in far from ideal regimes is it possible to probe such peculiar
features.
