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arXiv · 2311.13654

Universal Quantum Computation via Superposed Orders of Single-Qubit Gates

Kyrylo Simonov·Marcello Caleffi·Jessica Illiano·Jacquiline Romero·Angela Sara Cacciapuoti
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Abstract

Superposed orders of quantum channels have already been proved - both theoretically and experimentally - to enable unparalleled opportunities in the quantum communication domain. As a matter of fact, superposition of orders can be exploited within the quantum computing domain as well, by relaxing the (traditional) assumption underlying quantum computation about applying gates in a well-defined causal order. In this context, we address a fundamental question arising with quantum computing: whether superposed orders of single-qubit gates can enable universal quantum computation. As shown in this paper, the answer to this key question is a definitive "yes". Indeed, we prove that any two-qubit controlled quantum gate can be deterministically realized, including the so-called Barenco gate that alone enables universal quantum computation.

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Kyrylo Simonov, Marcello Caleffi, Jessica Illiano, Jacquiline Romero, Angela Sara Cacciapuoti. 2023-11-22. Universal Quantum Computation via Superposed Orders of Single-Qubit Gates. https://doi.org/10.1103/6xwr-9b4y

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