Misure massimizzanti l'informazione di Fisher nei sistemi quantistici

Abstract

Braunstein and Caves (1994) showed that Helstrom's quantum information maximises expected Fisher information over all possible measurements on a given quantum system. For one-dimensional parameter pure state system, we derived necessary and/or sufficient conditions for measurement in order to be a maximising one, according to some assumptions either on the dimension of the physical space of the system or on the kind of measurement to be applied.