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arXiv · 2102.13596

A Reconfigurable Quantum Local Area Network Over Deployed Fiber

Muneer Alshowkan·Brian P. Williams·Philip G. Evans·Nageswara S. V. Rao·Emma M. Simmerman·Hsuan-Hao Lu·Navin B. Lingaraju·Andrew M. Weiner·Claire E. Marvinney·Yun-Yi Pai·Benjamin J. Lawrie·Nicholas A. Peters·Joseph M. Lukens
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Abstract

Practical quantum networking architectures are crucial for scaling the connection of quantum resources. Yet quantum network testbeds have thus far underutilized the full capabilities of modern lightwave communications, such as flexible-grid bandwidth allocation. In this work, we implement flex-grid entanglement distribution in a deployed network for the first time, connecting nodes in three distinct campus buildings time-synchronized via the Global Positioning System (GPS). We quantify the quality of the distributed polarization entanglement via log-negativity, which offers a generic metric of link performance in entangled bits per second. After demonstrating successful entanglement distribution for two allocations of our eight dynamically reconfigurable channels, we demonstrate remote state preparation -- the first realization on deployed fiber -- showcasing one possible quantum protocol enabled by the distributed entanglement network. Our results realize an advanced paradigm for managing entanglement resources in quantum networks of ever-increasing complexity and service demands.

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Muneer Alshowkan, Brian P. Williams, Philip G. Evans, Nageswara S. V. Rao, Emma M. Simmerman, Hsuan-Hao Lu, Navin B. Lingaraju, Andrew M. Weiner, Claire E. Marvinney, Yun-Yi Pai, Benjamin J. Lawrie, Nicholas A. Peters, Joseph M. Lukens. 2021-02-26. A Reconfigurable Quantum Local Area Network Over Deployed Fiber. https://doi.org/10.1103/prxquantum.2.040304

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