Many-spin entanglement is investigated in one-dimensional zigzag chains, consisting of up to 12 spins 1/2, with nearest neighbor and next nearest neighbor interactions at high and low temperatures. We consider multiple quantum (MQ) nuclear magnetic resonance (NMR) dynamics. The second moment of the distribution of MQ coherences, which provides a lower bound on the quantum Fisher information, is calculated for different temperatures and evolution times. The dependence of the number of the entangled spins on the temperature and the chain length is obtained.

中文翻译：

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多量子核磁共振中锯齿形自旋链中的多自旋纠缠

在一维锯齿形链中研究了多自旋纠缠，该链由多达 12 个自旋 1/2 组成，在高温和低温下具有最近邻和次近邻相互作用。我们考虑多量子 (MQ) 核磁共振 (NMR) 动力学。MQ 相干分布的二阶矩提供了量子 Fisher 信息的下界，是针对不同的温度和演化时间计算的。获得了纠缠自旋数对温度和链长的依赖性。