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On the most efficient unitary transformation for programming quantum channels

Giacomo Mauro D'Ariano·Paolo Perinotti
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Abstract

We address the problem of finding the optimal joint unitary transformation on system + ancilla which is the most efficient in programming any desired channel on the system by changing the state of the ancilla. We present a solution to the problem for dim(H)=2 for both system and ancilla.

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Giacomo Mauro D'Ariano, Paolo Perinotti. 2005-09-26. On the most efficient unitary transformation for programming quantum channels. https://arxiv.org/abs/quant-ph/0509183

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