Sub-Poissonian photon statistics in a strongly coupled single-qubit   laser
  We investigate qubit lasing in the strong coupling limit. The qubit is given by a Cooper-pair box, and population inversion is established by an additional third state, which can be addressed via quasiparticle tunneling. The coupling strength between oscillator and qubit is assumed to be much higher than the quasiparticle tunneling rate. We find that the photon number distribution is sub-Poissonian in this strong coupling limit. 
M. Marthaler, Pei-Qing Jin, Juha Lepp\"akangas and Gerd Sch\"on
cond-mat.mes-hall