State estimation from a pair of conjugate qudits
Xiang-Fa Zhou, Yong-Sheng Zhang, Guang‐Can Guo · Physical Review A · 2006
We show that, for $N$ parallel input states, an antilinear map with respect to a specific basis is essentially a classical operation. We also consider the information contained in a phase-conjugate pair $\ensuremath{\mid}\ensuremath{\phi}⟩\ensuremath{\mid}{\ensuremath{\phi}}^{*}⟩$, and prove that there is more information about a quantum state encoded in a phase-conjugate pair than in a parallel pair.