Cavity QED systems with group II atoms and the crossover between lasing and superradiance

Recently, cavity QED systems with an optical transition with a decay rate many orders of magnitude smaller than than normal dipole allowed optical transitions have been realized experimentally. These new systems allow access to investigate the crossover between lasing and superradiance. We model such systems theoretically using a master equation, and solve this equation using the quantum state diffusion algorithm. We discuss the statistical properties of the generated light. A solid understanding of this crossover regime could allow us to transplant some of the knowledge and methods from the laser side to the steady steady superradiance side, where we have recently demonstrated the possibility of a mHz linewidth light source.