Quantum state discrimination; post-measurement information; Optimal measurement
Issue Date
2022-02
Publisher
Kluwer Academic Publishers
Citation
Quantum Information Processing, v. 21, NO. 2, article no. 64, Page. 1-26
Abstract
We consider the optimal discrimination of nonorthogonal qubit states with post-measurement information and provide an analytic structure of the optimal measurements. We also show that there is always a optimal measurement when post-measurement information is given. Further, in discriminating four states using post-measurement information, we analytically provide the optimal probability of correct guessing and show that the uniqueness of optimal measurement is equivalent to the non-existence of non- optimal measurement with post-measurement information.