Population trapping due to cavity losses

In population trapping the occupation of a decaying quantum level keeps a constant nonzero value. We show that an atom-cavity system interacting with an environment characterized by a nonflat spectrum, in the non-Markovian limit, exhibits such a behavior, effectively realizing the preservation of nonclassical states against dissipation. Our results allow us to understand the role of cavity losses in hybrid solid state systems and pave the way to the proper description of leakage in the recently developed cavity quantum electrodynamic systems.