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Minimal disturbance measurement for coherent states is non-Gaussian

Ladislav Mišta Jr
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Abstract

In standard coherent state teleportation with shared two-mode squeezed vacuum (TMSV) state there is a trade-off between the teleportation fidelity and the fidelity of estimation of the teleported state from results of the Bell measurement. Within the class of Gaussian operations this trade-off is optimal, i.e. there is not a Gaussian operation which would give for a given output fidelity a larger estimation fidelity. We show that this trade-off can be improved by up to 2.77% if we use a suitable non-Gaussian operation. This operation can be implemented by the standard teleportation protocol in which the shared TMSV state is replaced with a suitable non-Gaussian entangled state. We also demonstrate that this operation can be used to enhance the transmission fidelity of a certain noisy channel.

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Ladislav Mišta Jr. 2006-01-26. Minimal disturbance measurement for coherent states is non-Gaussian. https://doi.org/10.1103/physreva.73.032335

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