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arXiv · 0810.3211

Realization schemes for quantum instruments in finite dimensions

Giulio Chiribella·Giacomo Mauro D'Ariano·Paolo Perinotti
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Abstract

We present a general dilation scheme for quantum instruments with continuous outcome space in finite dimensions, in terms of an indirect POVM measurement performed on a finite dimensional ancilla. The general result is then applied to a large class of instruments generated by operator frames, which contains group-covariant instruments as a particular case, and allows to construct dilation schemes based on a measurement on the ancilla followed by a conditional feed-forward operation on the output. In the case of tight operator frames our construction generalizes quantum teleportation and telecloning, producing a whole family of generalized teleportation schemes in which the instrument is realized via a joint POVM at the sender combined with a conditional feed-forward operation at the receiver.

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Giulio Chiribella, Giacomo Mauro D'Ariano, Paolo Perinotti. 2009-04-14. Realization schemes for quantum instruments in finite dimensions. https://doi.org/10.1063/1.3105923

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