Study of the magnetic phase transitions of La3MnBi5 using muon spin relaxation

The Ln3MnBi5 series, featuring isolated MnBi6 spin chains, offers a pristine platform to study this interplay. Recent work on La3MnBi5 reveals complex phase transitions below 50 K, with antiferromagnetic correlations, hysteretic magnetoresistance, and metallic conductivity—hinting at intertwined spin and charge dynamics. However, the microscopic nature of its magnetic ground state remains unresolved, particularly the role of interchain hybridization and possible competing orders. Muon spin relaxation is uniquely suited to probe such systems, as it can detect local field distributions, dynamic fluctuations, and hidden transitions insensitive to bulk techniques. Here, we propose μSR studies of La3MnBi5 to unravel its low-dimensional magnetism and clarify the mechanisms driving its anomalous transitions.

Ln₃MnBi₅系列具有孤立的MnBi₆自旋链（spin chains），为探究此类相互作用提供了本征纯净的理想研究平台。针对La₃MnBi₅的近期研究表明，其在50K以下存在复杂相变，伴随反铁磁关联（antiferromagnetic correlations）、迟滞磁电阻（hysteretic magnetoresistance）与金属导电性（metallic conductivity），暗示自旋与电荷动力学存在相互交织的关联。然而其磁性基态的微观本质仍未明确，尤其是链间杂化（interchain hybridization）与潜在竞争序（competing orders）所发挥的作用。缪子自旋弛豫（Muon spin relaxation）技术非常适用于此类体系的探测，因其能够检测局域场分布、动态涨落以及体相技术无法感知的隐藏相变。本文拟通过μSR研究La₃MnBi₅，以阐明其低维磁性，并揭示驱动其反常相变的内在机制。