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arXiv · 2506.22114

Perfect quantum state transfer through a chaotic spin chain via many-body scars

Shane Dooley·Luke Johnston·Patrick Gormley·Beth Campbell
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Abstract

Quantum many-body scars (QMBS) offer a mechanism for weak ergodicity breaking, enabling non-thermal dynamics to persist in a chaotic many-body system. While most studies of QMBS focus on anomalous eigenstate properties or long-lived revivals of local observables, their potential for quantum information processing remains largely unexplored. In this work, we demonstrate that \emph{perfect quantum state transfer} can be achieved in a strongly interacting, quantum chaotic spin chain by exploiting a sparse set of QMBS eigenstates embedded within an otherwise thermal spectrum. These results show that QMBS in chaotic many-body systems may be harnessed for information transport tasks typically associated with integrable models.

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Shane Dooley, Luke Johnston, Patrick Gormley, Beth Campbell. 2025-06-27. Perfect quantum state transfer through a chaotic spin chain via many-body scars. https://doi.org/10.1103/hdy9-dr9m

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