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arXiv · 2507.06305

Entanglement switching via mobility edges in a quasiperiodic chain

YouYoung Joung·Junmo Jeon·SungBin Lee
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Abstract

We propose quasiperiodic chains with tunable mobility edge physics, as a promising platform for engineering long-range quantum entanglement. Using the generalized Aubry-Andr\'e model, we show that the mobility edges play a key role in manipulating long-range indirect interactions in these systems. Near the mobility edge, critical states exhibit unexpectedly strong correlations between sites that share similar local structures, regardless of their spatial separation. Remarkably, by tuning the mobility edge across the Fermi level, one can induce both adiabatic transport and abrupt switching of entanglement between distant sites. These results highlight the potential of aperiodic structures for controlling nonlocal quantum correlations, opening new avenues for entanglement-based applications in quasiperiodic systems.

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YouYoung Joung, Junmo Jeon, SungBin Lee. 2025-07-08. Entanglement switching via mobility edges in a quasiperiodic chain. https://arxiv.org/abs/2507.06305

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