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arXiv · 2205.02782

Long-Range Bell States from Local Measurements and Many-Body Teleportation without Time-Reversal

Lakshya Agarwal·Christopher M. Langlett·Shenglong Xu
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Abstract

In this work, we study quantum many-body teleportation, where a single qubit is teleported through a strongly-interacting quantum system, as a result of a scrambling unitary and local measurements on a few qubits. Usual many-body teleportation protocols require a double copy of the system, and backward time evolution, we demonstrate that teleportation is possible in the 2D spin-$1/2$ XY model, without these constraints. The necessary long-range entanglement for teleportation is generated from the model hosting special eigenstates known as rainbow scars. We outline a specific protocol for preparing this highly entangled state by evolving a product state and performing iterative measurements on only two qubits with feedback control.

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Lakshya Agarwal, Christopher M. Langlett, Shenglong Xu. 2022-12-05. Long-Range Bell States from Local Measurements and Many-Body Teleportation without Time-Reversal. https://doi.org/10.1103/physrevlett.130.020801

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