Diluted maximum-likelihood algorithm for quantum tomography
  We propose a refined iterative likelihood-maximization algorithm for reconstructing a quantum state from a set of tomographic measurements. The algorithm is characterized by a very high convergence rate and features a simple adaptive procedure that ensures likelihood increase in every iteration and convergence to the maximum-likelihood state.   We apply the algorithm to homodyne tomography of optical states and quantum tomography of entangled spin states of trapped ions and investigate its convergence properties. 
Jaroslav Rehacek, Zdenek Hradil, E. Knill, A. I. Lvovsky