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arXiv · 2407.02858

Teleporting two-qubit entanglement across 19 qubits on a superconducting quantum computer

Haiyue Kang·John F. Kam·Gary J. Mooney·Lloyd C. L. Hollenberg
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Abstract

Quantum teleportation is not merely a fascinating corollary of quantum entanglement, it also finds utility in quantum processing and circuit compilation. In this paper, we measure and track the entanglement and fidelity of two-qubit states prepared on a 127-qubit IBM Quantum device, as one of the qubits is teleported across 19 qubits. We design, evaluate and compare two distinct approaches to teleportation: post-selected measurement categorisation and dynamic circuit corrections based on mid-circuit measurements, and compare with direct state transportation using SWAP gates. By optimally choosing the teleportation path which exhibits the highest total negativity entanglement measure across nearest-neighbour pairs, we show the entanglement of a two-qubit graph state is sustained after at least 19 hops in teleportation using the post-selection approach and 17 hops using the dynamic circuit approach. We observe a higher level of teleported entanglement in paths determined from two-qubit negativities compared to those obtained from gate errors, demonstrating an advantage in using the negativity map over the gate error map for compiling quantum circuits.

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Haiyue Kang, John F. Kam, Gary J. Mooney, Lloyd C. L. Hollenberg. 2024-07-03. Teleporting two-qubit entanglement across 19 qubits on a superconducting quantum computer. https://doi.org/10.1103/physrevapplied.23.014057

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