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Qubit state guidance without feedback

Mauro Paternostro·M. S. Kim
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Abstract

We study a protocol for two-qubit state guidance that does not rely on feedback mechanisms. In our scheme, entanglement can be concentrated by arranging the interactions of the qubits with a continuous variable ancilla. By properly post-selecting the outcomes of repeated measurements of the state of the ancilla, the qubit state is driven to have a desired amount of purity and entanglement. We stress the primary role played by the first iterations of the protocol. Inefficiencies in the detection operations can be fully taken into account.

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Mauro Paternostro, M. S. Kim. 2004-10-04. Qubit state guidance without feedback. https://doi.org/10.1088/1367-2630%2F7%2F1%2F043

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