Identification and distance measures of measurement apparatus.
We propose simple schemes that can perfectly identify projective measurement apparatuses secretly chosen from a finite set. Entanglement is used in these schemes both to make possible the perfect identification and to improve the efficiency significantly. Based on these results, a brief discussion on the problem of how to appropriately define distance measures of measurements is also provided.
Ji
Zhengfeng
Z
State Key Laboratory of Intelligent Technology and Systems, Department of Computer Science and Technology, Tsinghua University, Beijing 100084, China. jizhengfeng98@mails.tsinghua.edu.cn
Feng
Yuan
Y
Duan
Runyao
R
Ying
Mingsheng
M