Damping of a quantum optical mode is in principle a simple subject. However, not all loss is the same. One example is the 50% lossy beam splitter (diagram on right shows experimental implementation) which rather than randomly deleting about half the photons in a beam, in fact can be made transparent or fully absorbing . More generally we are also investigating overdamped quantum systems via measurement models.
 T. Roger et al., Metamaterial Plasmonic Absorption in the Quantum Regime, Submitted.