Quantum gate broadcasting on graphs

Hiroki Sukeno; Tzu-Chieh Wei

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arXiv · 2503.10946

Quantum gate broadcasting on graphs

Hiroki Sukeno·Tzu-Chieh Wei

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Abstract

Given a known or unknown phase encoded in a higher-dimensional qudit gate, it is possible to send copies of a gate that encodes the phase to multiple receivers based on a generalized quantum teleportation. We extend this quantum gate broadcast protocol to a quantum network on directed acyclic graphs in which agents can add phase gates to be distributed and pass unknown phase gates to subsequent receivers. Similarly to the Greenberger-Horne-Zeilinger state, we show that the resource state can be efficiently prepared in finite time.

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Hiroki Sukeno, Tzu-Chieh Wei. 2025-03-13. Quantum gate broadcasting on graphs. https://arxiv.org/abs/2503.10946

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