Information-disturbance trade-off in quantum-state discrimination
Francesco Buscemi, Massimiliano Federico Sacchi · Physical Review A · 2006
When discriminating between two pure quantum states, there exists a quantitative trade-off between the information retrieved by the measurement and the disturbance caused on the unknown state. We derive the optimal trade-off and provide the corresponding quantum measurement. Such an optimal measurement smoothly interpolates between the two limiting cases of maximal information extraction and no measurement at all.