自旋-1/2链矢量手性关联中隐藏的多体纠缠
Multipartite entanglement hidden in vector-chiral correlations of spin-1/2 chains
- Okinawa Institute of Science and Technology Graduate University（冲绳科学技术大学院大学）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
该研究为自旋-1/2链建立矢量手性关联的量子Fisher信息界，证明其可表征多体纠缠深度，并通过多铁性材料的介电损耗谱实现实验探测。
AI中文摘要：
通过实验可观测的物理量来表征量子材料中的纠缠仍然是一个核心挑战。与单自旋算符之和相关联的量子Fisher信息提供了一条途径，将纠缠与可测量的磁响应函数联系起来。将这种方法扩展到局域复合观测量需要新的纠缠界。在此，我们为具有偶数格点数的周期性自旋-1/2链建立了最近邻总矢量手性的严格界。对于任何k-可制备态，每个自旋的量子Fisher信息不能超过k+1，因此超过此界即可证明纠缠深度至少为k+1。结合无限密度矩阵重整化群和热纯量子态计算，我们展示了在扩展的J1-J2 XXZ链中，零温和有限温度下矢量手性关联所编码的多体纠缠。矢量手性与电极化之间的自旋流耦合，原则上可通过多铁性磁体中的介电损耗谱来探测这一判据，将纠缠诊断扩展到偶极自旋关联之外。
英文摘要：
Characterizing entanglement in quantum materials through experimentally accessible observables remains a central challenge. Quantum Fisher information associated with sums of one-site spin operators provides one route by linking entanglement to measurable magnetic response functions. Extending this approach to local composite observables requires new entanglement bounds. Here we establish a rigorous bound for the total nearest-neighbour vector chirality of periodic spin-$1/2$ chains with an even number of sites. The quantum Fisher information per spin cannot exceed $k+1$ for any $k$-producible state, so exceeding this bound certifies entanglement depth of at least $k+1$. Combining infinite density-matrix renormalization group and thermal pure quantum-state calculations, we demonstrate multipartite entanglement encoded in vector-chiral correlations at zero and finite temperatures in an extended $J_1$-$J_2$ XXZ chain. The spin-current coupling between vector chirality and electric polarization offers, in principle, access to this witness through dielectric loss spectroscopy in multiferroic magnets, extending entanglement diagnostics beyond dipolar spin correlations.
