arXiv:0811.2360 · Physical Review A

Adaptive estimation of qubits by symmetry measurements

Christof J. Happ, Matthias Freyberger

Published Dec 12, 2008• 11 citations

Abstract

We analyze quantum state estimation for finite samples based on symmetry information. The measurement concept used compares an unknown qubit to a reference state. We describe explicitly an adaptive strategy that enhances the estimation fidelity of these measurements.

DOI: 10.1103/physreva.78.064303

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