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"path": "/papers/q-2026-02-23-2006/",
"publishedAt": "2026-02-23T12:35:42.000Z",
"site": "https://quantum-journal.org",
"tags": [
"Paper",
"https://doi.org/10.22331/q-2026-02-23-2006"
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"textContent": "Quantum 10, 2006 (2026).\n\nhttps://doi.org/10.22331/q-2026-02-23-2006\n\nWe propose modifying topological quantum error correcting codes by incorporating space-time defects, termed “time vortices,'' to reduce the number of physical qubits required to achieve a desired logical error rate. A time vortex is inserted by adding a spatially varying delay to the periodic measurement sequence defining the code such that the delay accumulated on a homologically non-trivial cycle is an integer multiple of the period. We analyze this construction within the framework of the Floquet color code and optimize the embedding of the code on a torus along with the choice of the number of time vortices inserted in each direction. Asymptotically, the vortexed code requires less than half the number of qubits as the vortex-free code to reach a given code distance. We benchmark the performance of the vortexed Floquet color code by Monte Carlo simulations with a circuit-level noise model and demonstrate that the smallest vortexed code (with $30$ qubits) outperforms the vortex-free code with $42$ qubits.",
"title": "Increasing the distance of topological codes with time vortex defects"
}