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arXiv · 2401.04014

Non-adiabatic holonomies as photonic quantum gates

Vera Neef·Julien Pinske·Tom A. W. Wolterink·Karo Becker·Matthias Heinrich·Stefan Scheel·Alexander Szameit
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Abstract

One of the most promising nascent technologies, quantum computation faces a major challenge: The need for stable computational building blocks. We present the quantum-optical realization of non-adiabatic holonomies that can be used as single-qubit quantum gates. The hallmark topological protection of non-Abelian geometric phases reduces the need for quantum error correction on a fundamental physical level, while the inherent non-adiabaticity of the structures paves the way for unprecedented miniaturization. To demonstrate their versatility, we realize the Hadamard and Pauli-X gates, experimentally show their non-Abelian nature, and combine them into a single-qubit quantum algorithm, the PQ penny flipover. The planar geometry of such designs enables them to be substituted for the conventional directional coupler meshes currently in wide-spread use in photonic quantum architectures across all platforms.

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Vera Neef, Julien Pinske, Tom A. W. Wolterink, Karo Becker, Matthias Heinrich, Stefan Scheel, Alexander Szameit. 2024-01-08. Non-adiabatic holonomies as photonic quantum gates. https://arxiv.org/abs/2401.04014

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