Almost Global Stochastic Feedback Stabilization of Conditional Quantum   Dynamics
  We propose several parametrization-free solutions to the problem of quantum state reduction control by means of continuous measurement and smooth quantum feedback. In particular, we design a feedback law for which almost global stochastic feedback stabilization can be proved analytically by means of Lyapunov techinques. This synthesis arises very naturally from the physics of the problem, as it relies on the variance associated with the quantum filtering process. 
Claudio Altafini and Francesco Ticozzi