The quantized electromagnetic field inside and outside an absorbing high-Q cavity is studied, with special emphasis on the absorption losses in the coupling mirror and their influence on the outgoing field. Generalized operator input-output relations are derived, which are used to calculate the Wigner function of the outgoing field. To illustrate the theory, the preparation of the outgoing field in a Schr\"{o}dinger cat-like state is discussed.
@article{arxiv.quant-ph/0512184,
title = {Quantum-state input-output relations for absorbing cavities},
author = {M. Khanbekyan and D. -G. Welsch and A. A. Semenov and W. Vogel},
journal= {arXiv preprint arXiv:quant-ph/0512184},
year = {2009}
}