量子自旋冰的缺陷毒化
Defect Poisoning of Quantum Spin Ice
- Helmholtz-Zentrum Berlin für Materialien und Energie（柏林赫尔姆霍兹材料能源中心）
- Freie Universität Berlin（柏林自由大学）
- University of Cambridge（剑桥大学）
- Boston University（波士顿大学）
- Harvard University（哈佛大学）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
该研究通过大规模量子蒙特卡洛模拟和精确对角化，发现磁性空位在低至2%的稀释水平下即可定性重塑量子自旋冰的低能行为，并可能掩盖其特征信号。
AI中文摘要：
寻找量子自旋冰的材料实现已推动二十多年的实验努力。候选材料不可避免地含有晶体缺陷，如磁性空位，其影响常被忽视。在此，我们表明，实验相关的稀释水平可以定性地重塑低能行为，因为邻近的空位会产生在纯净系统中不存在的量子涨落。即使在低至百分之二的稀释水平（远低于铈基烧绿石中报道的水平），这些空位诱导过程连接渗流自旋簇，并主导常规量子自旋冰动力学。因此，我们认为当前实验中的磁性空位可能强烈污染，甚至完全掩盖所寻求的量子自旋冰特征。我们利用大规模、无偏量子蒙特卡洛模拟和精确对角化支持这些结论。
英文摘要：
The hunt for a material realization of quantum spin ice has motivated more than two decades of experimental effort. The candidate materials inevitably contain crystal imperfections, such as magnetic vacancies, whose effects are often disregarded. Here, we show that experimentally relevant levels of dilution can qualitatively reshape the low-energy behavior, as nearby vacancies generate quantum fluctuations that are absent in the clean system. Already at dilution levels as low as two percent, well below those reported in cerium-based pyrochlores, these vacancy-induced processes connect percolating clusters of spins and dominate over the conventional quantum-spin-ice dynamics. We therefore argue that magnetic vacancies in current experiments can strongly contaminate, and potentially completely obscure, the sought-after signatures of quantum spin ice. We support these conclusions using large-scale, unbiased quantum Monte Carlo simulations and exact diagonalization.
