Lüders channels and the existence of symmetric-informationally-complete measurements
John B. DeBrota, Blake C. Stacey
The L\"uders rule provides a way to define a quantum channel given a quantum measurement. Using this construction, we establish an if-and-only-if condition for the existence of a $d$-dimensional symmetric-informationally-complete quantum measurement (a SIC) in terms of a particular depolarizing channel. Moreover, the channel in question satisfies two entropic optimality criteria.
arXiv:1907.10999•Physical Review A•Dec 19, 2019•18 citations