发表机构
Barcelona Supercomputing Center（巴塞罗那超级计算中心）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究解决了两 parties 共享态的非局域魔精确量化问题，发现其与稳定子保真度及纠缠盗用任务相关，揭示临界链与随机单态非局域魔的差异，为量子关联研究提供操作可行的性质。
AI 中文摘要
魔（又称非稳定子性）是将Clifford电路提升为通用量子计算的资源，已成为多体态的标准诊断量。然而对于两 parties 共享的态，一个基础问题仍未解决：多少魔存在于 parties 间的关联而非其局域基中？分离该非局域魔需对所有局域基求极小，该优化问题至今无精确解。本文针对稳定子保真度解决了该问题：任意多qubit纯态的非局域魔是其纠缠谱与最近邻Bell对谱的距离。该量还支配着一项看似无关的任务：若且仅当某态的非局域魔发散时，该态族可通过局域操作与经典通信（LOCC）普遍盗用纠缠。关键性质并非纠缠量，而是纠缠谱在秩的2因子窗口间的权重分布方式：临界链与随机单态虽具有相同的对数纠缠标度，但分别携带无界和消失的非局域魔。非局域魔因此成为量子关联的操作上有意义的性质，可直接通过张量网络模拟获取，并可通过纠缠谱学应用于实验。
英文摘要
Magic, or nonstabilizerness, is the resource that lifts Clifford circuits to universal quantum computation and has become a standard diagnostic of many-body states. For a state shared between two parties, however, a basic question has remained open: how much of the magic resides in the correlations between the parties rather than in their local bases? Isolating this nonlocal magic requires minimizing over all local bases, an optimization that has so far resisted exact solution. Here we solve it for the stabilizer fidelity: the nonlocal magic of every pure multiqubit state is the distance of its entanglement spectrum from the closest spectrum of Bell pairs. The same quantity governs an apparently unrelated task: a family of states universally embezzles entanglement under local operations and classical communication if and only if its nonlocal magic diverges. The deciding property is not the amount of entanglement but the way the entanglement spectrum spreads its weight across factor-of-two windows of rank, so that critical chains and random-singlet states, with identical logarithmic entanglement scaling, carry unbounded and vanishing nonlocal magic, respectively. Nonlocal magic thereby becomes an operationally meaningful property of quantum correlations, directly accessible to tensor-network simulations and, through entanglement spectroscopy, to experiments.
Comments18 pages, 3 figures, comments welcome!
