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Realization of Universal Optimal Quantum Machines by Projective Operators and Stochastic Maps

F. Sciarrino·C. Sias·M. Ricci·F. De Martini
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Abstract

Optimal quantum machines can be implemented by linear projective operations. In the present work a general qubit symmetrization theory is presented by investigating the close links to the qubit purification process and to the programmable teleportation of any generic optimal anti-unitary map. In addition, the contextual realization of the N ->M cloning map and of the teleportation of the N->(M-N) universal NOT gate is analyzed by a novel and very general angular momentum theory. An extended set of experimental realizations by state symmetrization linear optical procedures is reported. These include the 1->2 cloning process, the UNOT gate and the quantum tomographic characterization of the optimal partial transpose map of polarization encoded qubits.

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F. Sciarrino, C. Sias, M. Ricci, F. De Martini. 2004-07-22. Realization of Universal Optimal Quantum Machines by Projective Operators and Stochastic Maps. https://doi.org/10.1103/physreva.70.052305

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