We discuss the criteria presently used for evaluating the efficiency of quantum teleportation schemes for continuous variables. Using an argument based upon the difference between 1-to-2 quantum cloning (quantum duplication) and 1-to-infinity cloning (classical measurement), we show that a fidelity value larger than 2/3 is required for successful quantum teleportation of coherent states. This value has not been reached experimentally so far.
@article{arxiv.quant-ph/0012121,
title = {No-cloning theorem and teleportation criteria for quantum continuous variables},
author = {Frédéric Grosshans and Philippe Grangier},
journal= {arXiv preprint arXiv:quant-ph/0012121},
year = {2016}
}