The possibility to induce a macroscopic magnetic moment in lead halide perovskites (LHPs), combined with their excellent optoelectronic properties, is of fundamental interest and has promising spintronic applications. However, these possibilities remain an open question in both theory and experiment. Here, theoretical and experimental studies are performed to explore ferromagnetic states in LHPs originated from lattice defects. First-principle calculations reveal that shallow-level Br vacancies in defective CsPbBr₃ can produce spin-splitting states and the coupling between them leads to a ferromagnetic ground state. Experimentally, ferromagnetism at 300 K is observed in room-temperature synthesized CsPbBr₃ nanocrystals, but is not observed in hot-injection prepared CsPbBr₃ quantum dots and in CsPbBr₃ single crystals, highlighting the significance played by vacancy defects. Furthermore, the ferromagnetism in the CsPbBr₃ nanocrystals can be enhanced fourfold with Ni²⁺ ion dopants, due to enhancement of the exchange coupling between magnetic polarons. Room-temperature ferromagnetism is also observed in other LHPs, which suggests that vacancy-induced ferromagnetism may be a universal feature of solution-processed LHPs, which is useful for future spintronic devices.

在卤化铅钙钛矿 (LHP) 中诱导宏观磁矩的可能性，以及它们出色的光电特性，具有根本性的意义，并具有前景广阔的自旋电子学应用。然而，这些可能性在理论和实验中仍然是一个悬而未决的问题。在这里，进行理论和实验研究以探索 LHP 中源自晶格缺陷的铁磁状态。第一性原理计算表明，有缺陷的 CsPbBr ₃中的浅能级 Br 空位可以产生自旋分裂态，并且它们之间的耦合导致铁磁基态。实验上，在室温合成的 CsPbBr ₃纳米晶体中观察到 300 K 的铁磁性，但在热注射制备的 CsPbBr 中未观察到_{3 个}量子点和 CsPbBr ₃单晶中，突出了空位缺陷的重要性。此外，由于增强了磁极化子之间的交换耦合，CsPbBr ₃纳米晶体中的铁磁性可以通过Ni ^{2+离子掺杂剂增强四倍。}在其他 LHP 中也观察到室温铁磁性，这表明空位诱导的铁磁性可能是溶液处理 LHP 的普遍特征，这对未来的自旋电子器件很有用。