A note on the measures of process fidelity for non-unitary quantum   operations
  Various fidelity measures can be defined between two quantum processes especially when at least one of them is non-unitary. In this paper we consider two such measures of state averaged process fidelity, put forward an efficient procedure to compute them and investigate their mathematical properties as well as their relationship. 
Joydip Ghosh
math-ph math.MP quant-ph