A quantum stochastic calculus approach to modeling double-pass   atom-field coupling
  We examine a proposal by Sherson and Moelmer to generate polarization-squeezed light in terms of the quantum stochastic calculus (QSC). We investigate the statistics of the output field and confirm their results using the QSC formalism. In addition, we study the atomic dynamics of the system and find that this setup can produce up to 3 dB of atomic spin squeezing. 
Gopal Sarma, Andrew Silberfarb, and Hideo Mabuchi