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Estimation of qubit states in a factorizing basis

Th. Hannemann·D. Reiss·Ch. Balzer·W. Neuhauser·P. E. Toschek·Ch. Wunderlich
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Abstract

The optimal estimation of a quantum mechanical 2-state system (qubit) - with N identically prepared qubits available - is obtained by measuring all qubits simultaneously in an entangled basis. We report the experimental estimation of qubits using a succession of N measurements on individual qubits where the measurement basis is changed during the estimation procedure conditioned on the outcome of previous measurements (self-learning estimation). The performance of this adaptive algorithm is compared with other algorithms using measurements in a factorizing basis.

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Th. Hannemann, D. Reiss, Ch. Balzer, W. Neuhauser, P. E. Toschek, Ch. Wunderlich. 2001-10-10. Estimation of qubit states in a factorizing basis. https://arxiv.org/abs/quant-ph/0110068

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