Large teleportation of two-qubit state between non-neighboring nodes based on the utilization of multiple cluster states within quantum networks

Abstract

Abstract The transmission of quantum states over extended distances is constrained by photon losses, ruling
out direct amplification akin to classical telecommunications due to the non-cloning theorem. Overcoming
this challenge involves implementing quantum repeater protocols that leverage entanglement swapping to
create long-distance entanglement from shorter distances. A novel multi-hop quantum teleportation scheme,
blending concepts from quantum repeaters and teleportation, is under exploration. It aims to transfer
arbitrary two-qubit states between two distant parties, even in the absence of a direct quantum channel.
Intermediate nodes, connected via a four-qubit entangled cluster state as quantum channels, are introduced
based on a more general routing protocol. Bell measurements are independently conducted by the source
node (Alice) and all intermediate nodes, with simultaneous transmission of measurement results, significantly
reducing time consumption. Determining the quantum state from Bell measurement results requires only
the destination node (Bob) for a simple unitary transformation. Moreover, this protocol holds promise for
implementation on the IBM Quantum Experience platform once the requisite quantum circuits are designed.
This overview encompasses both the theoretical and experimental status of the proposed scheme, with
experimental findings incorporated into quantum state tomography to verify the accuracy of the transmitted quantum state.