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arXiv · 2610.03408

Subdimensional linear-optical quantum computation: from qudit resource states to qubit quantum computation

Tomohiro Yamazaki
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Abstract

In this paper, we propose a linear-optical quantum computation scheme that starts from high-dimensionally entangled qudits but performs quantum computation on qubits defined in their subspaces. This approach enables us to increase the success probability of linear-optical fusions from $50\%$ to $1-1/d$ for qudits of dimension $d$ without relying on existing approaches using ancilla photons and quantum codes. In particular, we show that a 2D cluster state of qubits can be generated from 5-qudit 1D cluster states using pairwise fusion gates while preserving their boosted success probability. We numerically demonstrate that this approach can improve the loss tolerance of a percolation-based scheme while keeping the photon number per resource state constant.

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Tomohiro Yamazaki. 2026-10-02. Subdimensional linear-optical quantum computation: from qudit resource states to qubit quantum computation. https://arxiv.org/abs/2610.03408

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