Information and fidelity in projective measurements

Hiroaki Terashima

Published 2011-09-13, updated 2012-01-07Version 2

In this study, we explicitly calculate information and fidelity of an r-rank projective measurement on a completely unknown state in a d-dimensional Hilbert space. We also show a tradeoff between information and fidelity at the level of a single outcome and discuss the efficiency of measurement with respect to fidelity.