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arXiv · 2609.07198

Remote Flux Refocuses Nonadiabatic Excursions in Compact-State Quantum Transfer

X. S. Meng·Y. S. Liu·X. Z. Zhang
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Abstract

Compact states embedded in a propagating band can carry quantum information, but finite-time transfer can populate modes outside their subspace. We show that a remote flux can refocus this amplitude without changing the transfer states or the motion-induced coupling out of their subspace. In a resonator ring, this separation is exact because both endpoints of the flux-bearing bond are nodes of every compact transfer state. For the same pulse, zero and refocusing flux both produce substantial excursions, but only the latter yields near-complete logical transfer. Interference between matrix amplitudes associated with different windings suppresses the endpoint error. Under matched control bounds, numerical optimization yields higher worst-input fidelity at the refocusing flux, providing a route to accurate transfer through coherent return.

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X. S. Meng, Y. S. Liu, X. Z. Zhang. 2026-09-07. Remote Flux Refocuses Nonadiabatic Excursions in Compact-State Quantum Transfer. https://arxiv.org/abs/2609.07198

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