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arXiv · 1710.04311

A noisy channel less entangled than a pure can improve teleportation

Luis Roa·M. Loreto Ladrón de Guevara·Matias Soto-Moscoso·Pamela Catalán
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Abstract

In our work we consider the following problem in the context of teleportation: an unknown pure state have to be teleported and there are two laboratories which can perform the task. One laboratory uses a pure non maximally entangled channel but has a capability of performing the joint measurement on bases with a constrained degree of entanglement; the other lab makes use of a mixed X-state channel but can perform a joint measurement on bases with higher entanglement degrees. We compare the average teleportation fidelity achieved in both cases, finding that the fidelity achieved with the X-state can surpass the obtained with a pure channel, even though the X-state is less entangled than the latter. We find the conditions under which this effect occurs. Our results evidence that the entanglement of the joint measurement plays a role as important as the entanglement of the channel in order to optimize the teleportation process. We include an example showing that the average fidelity of teleportation obtained with a Werner state channel can be grater than that obtained with a Bell state channel.

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Luis Roa, M. Loreto Ladrón de Guevara, Matias Soto-Moscoso, Pamela Catalán. 2017-10-24. A noisy channel less entangled than a pure can improve teleportation. https://arxiv.org/abs/1710.04311

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