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arXiv · 2508.14641

High-fidelity realisation of CNOT gate in Majorana-based optical platform

Jia-Kun Li·Kai Sun·Ze-Yan Hao·Jia-He Liang·Jiannis K. Pachos·Lucy Byles·Jin-Shi Xu·Yong-Jian Han·Chuan-Feng Li·Guang-Can Guo
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Abstract

We present the experimental realisation of a robust CNOT quantum gate using Majorana zero modes simulated on a photonic platform. Three Kitaev chains supporting Majorana zero modes at their endpoints are used to encode two logical qubits, and both intra-chain and inter-chain braiding operations are performed to implement the CNOT gate. While the topological encoding of quantum information in Majorana fermions does not offer full topological protection in our non-interacting photonic setting, it nevertheless exhibits a natural resilience to the dominant noise and decoherence effects present in the experiment. Consequently, the fidelity of the CNOT gate is significantly enhanced, surpassing 0.992 and addressing a key limitation in the path toward scalable quantum computation. These results represent a major advancement in topological quantum computing with Majorana fermions and underscore the potential of photonic platforms for realising high-fidelity quantum gates.

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Jia-Kun Li, Kai Sun, Ze-Yan Hao, Jia-He Liang, Jiannis K. Pachos, Lucy Byles, Jin-Shi Xu, Yong-Jian Han, Chuan-Feng Li, Guang-Can Guo. 2025-08-20. High-fidelity realisation of CNOT gate in Majorana-based optical platform. https://arxiv.org/abs/2508.14641

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