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arXiv · 2506.11236

Configuration design of multimode Gaussian operations on continuous-variable quad-rail lattice cluster states

Jun-ichi Yoshikawa·Warit Asavanant·Hironari Nagayoshi·Atsushi Sakaguchi·Shota Yokoyama·Hidehiro Yonezawa·Akira Furusawa
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Abstract

Continuous-variable quad-rail lattice cluster states enable flexible quantum circuit design on their two-dimensional structure. However, how to combine basic operations on the quad-rail lattice cluster state to realize multimode operations has not been deeply discussed. Here we show a concrete configuration design to efficiently implement beamsplitter network operations on the cluster state. Furthermore, combining the beamsplitter networks, a configuration design of multimode Gaussian unitary operations is also shown. It is theoretically known that the Gaussian operations are sufficient for universal quantum computation if appropriate non-Gaussian states are injected. Our results are fundamentally important for utilizing the flexible quad-rail lattice cluster states for computations.

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Jun-ichi Yoshikawa, Warit Asavanant, Hironari Nagayoshi, Atsushi Sakaguchi, Shota Yokoyama, Hidehiro Yonezawa, Akira Furusawa. 2025-06-12. Configuration design of multimode Gaussian operations on continuous-variable quad-rail lattice cluster states. https://arxiv.org/abs/2506.11236

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