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arXiv · 2202.00841

On the Teleportation of Discrete Variable Qubits Via Continuous Variable Lossy Channels

Mingjian He·Robert Malaney·Ryan Aguinaldo
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Abstract

The Continuous-Variable (CV) quantum state of light allows for the teleportation of a Discrete-Variable (DV) photonic qubit. Such an operation is useful in the realm of hybrid quantum networks. However, it is known that the teleportation of a DV qubit via a Gaussian CV resource channel is severely limited under channel loss, with a teleportation fidelity beyond the classical limit unattainable for losses exceeding a small threshold of 0.5 dB. In this work, we present a new non-deterministic teleportation protocol that combines a Gaussian CV resource channel with a modified form of the Bell State Measurement that accommodates a DV-qubit fidelity beyond the classical limit for channel losses up to 20~dB. Beyond this orders of magnitude improvement, we also show how the use of non-Gaussian operations on the CV resource channel can lead to a DV-qubit fidelity approaching unity for any channel loss.

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Mingjian He, Robert Malaney, Ryan Aguinaldo. 2022-02-02. On the Teleportation of Discrete Variable Qubits Via Continuous Variable Lossy Channels. https://doi.org/10.1103/physreva.105.062407

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