Informational power of quantum measurements

Michele Dall'Arno, Giacomo Mauro D'Ariano, Massimiliano F. Sacchi
2011 Physical Review A. Atomic, Molecular, and Optical Physics  
We introduce the informational power of a quantum measurement as the maximum amount of classical information that the measurement can extract from any ensemble of quantum states. We prove the additivity by showing that the informational power corresponds to the classical capacity of a quantum-classical channel. We restate the problem of evaluating the informational power as the maximization of the accessible information of a suitable ensemble. We provide a numerical algorithm to find an optimal ensemble, and quantify the informational power.
doi:10.1103/physreva.83.062304 fatcat:sdun73z5y5dutnrdastc4rykhe