# IPACS Electronic library

## Optimal unambiguous discrimination problems under different a priori knowledge

Ming Zhang, Lin, Dai, Zongtan Zhou, Dewen Hu
We have recently explored optimum unambiguous discrimination problems under different a prioriknowledge. In general, a priori knowledge in optimum unambiguous discrimination problems can be classed into two types: a priori knowledge of discriminated states themselves and \emph{a priori} probabilities of preparing the states. It is further clarified that no matter whether a priori probabilities of preparing discriminated states are available or not, what type of discriminators one should design just depends on what kind of the knowledge of discriminated states. This is in contrast to the observation that choosing the parameters of discriminators relies on both types of a priori knowledge.