Keldysh field theory for driven open quantum systems.

@article{Sieberer2016KeldyshFT,
  title={Keldysh field theory for driven open quantum systems.},
  author={Lukas M. Sieberer and M. Buchhold and Sebastian Diehl},
  journal={Reports on progress in physics. Physical Society},
  year={2016},
  volume={79 9},
  pages={
          096001
        }
}
Recent experimental developments in diverse areas-ranging from cold atomic gases to light-driven semiconductors to microcavity arrays-move systems into the focus which are located on the interface of quantum optics, many-body physics and statistical mechanics. They share in common that coherent and driven-dissipative quantum dynamics occur on an equal footing, creating genuine non-equilibrium scenarios without immediate counterpart in equilibrium condensed matter physics. This concerns both… 
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