Colossal Zero-Field-Cooled Exchange Bias via Tuning Compensated Ferrimagnetic in Kagome Metals

• Published in: Journal of the American Chemical Society Vol. 146; no. 30; pp. 20770 - 20777
• Main Authors: Zhou, Haowei, Cao, Yili, Khmelevskyi, Sergii, Zhang, Qinghua, Hu, Shixin, Avdeev, Maxim, Wang, Chin-Wei, Zhou, Rui, Yu, Chengyi, Chen, Xin, Li, Qiheng, Miao, Jun, Li, Qiang, Lin, Kun, Xing, Xianran
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 31.07.2024
• ISSN: 0002-7863; 1520-5126; 1520-5126
• DOI: 10.1021/jacs.4c04173

Exchange bias (EB) is a crucial property with widespread applications but particularly occurs by complex interfacial magnetic interactions after field cooling. To date, intrinsic zero-field-cooled EB (ZEB) has only emerged in a few bulk frustrated systems and their magnitudes remain small yet. Here, enabled by high temperature synthesis, we uncover a colossal ZEB field of 4.95 kOe via tuning compensated ferrimagnetism in a family of kagome metals, which is almost twice the magnitude of known materials. Atomic-scale structure, spin dynamics, and magnetic theory revealed that these compensated ferrimagnets originate from significant antiferromagnetic exchange interactions embedded in the holmium–iron ferrimagnetic matrix due to supersaturated preferential manganese doping. A random antiferromagnetic order of manganese sublattice sandwiched between ferromagnetic iron kagome bilayers accounts for such unconventional pinning. The outcome of the present study outlines disorder-induced giant bulk ZEB and coercivity in layered frustrated systems.