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Quantum signal splitting that avoids initialization of the targets

Dima Mozyrsky·Vladimir Privman
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Abstract

The classical signal splitting and copying are not possible in quantum mechanics. Specifically, one cannot copy the basis up and down states of the input (I) two-state system (qubit, spin) into the copy (C) and duplicate-copy (D) two-state systems if the latter systems are initially in an arbitrary state. We consider instead a quantum evolution in which the basis states of I at time t are duplicated in at least two of the systems I, C, D, at time t + Delta t. In essence, the restriction on the initial target states is exchanged for uncertainty as to which two of the three qubits retain copies of the initial source state.

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Dima Mozyrsky, Vladimir Privman. 1997-08-31. Quantum signal splitting that avoids initialization of the targets. https://doi.org/10.1142/s0217984997001523

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