2011年2月17日，我室低维物理与化学研究部李晓光教授研究组与新加坡南洋理工大学合作在PHYSICAL REVIEW LETTERS上发表题为Large Exchange Bias after Zero-Field Cooling from an Unmagnetized State的论文。

Source: PHYSICAL REVIEW LETTERS Volume: 106 Issue: 7 Article Number: 077203 Published: FEB 17 2011

Wang BM (Wang, B. M.)1, Liu Y (Liu, Y.)1, Ren P (Ren, P.)2, Xia B (Xia, B.)2, Ruan KB (Ruan, K. B.)2, Yi JB (Yi, J. B.)3, Ding J (Ding, J.)3, Li XG (Li, X. G.)4,5, Wang L (Wang, L.)2
Addresses:
1. Nanyang Technol Univ, Sch Mech & Aerosp Engn, Singapore 639798, Singapore
2. Nanyang Technol Univ, Sch Phys & Math Sci, Div Phys & Appl Phys, Singapore 637371, Singapore
3. Natl Univ Singapore, Dept Mat Sci & Engn, Singapore 119260, Singapore
4. Univ Sci & Technol China, Hefei Natl Lab Phys Sci Microscale, Hefei 230026, Peoples R China
5. Univ Sci & Technol China, Dept Phys, Hefei 230026, Peoples R China
E-mail Addresses: MLiuY@ntu.edu.sg, WangLan@ntu.edu.sg

Reprint Address: Wang, BM (reprint author), Nanyang Technol Univ, Sch Mech & Aerosp Engn, Singapore 639798, Singapore

Abstract:
Exchange bias (EB) is usually observed in systems with an interface between different magnetic phases after field cooling. Here we report an unusual phenomenon in which a large EB can be observed in Ni-Mn-In bulk alloys after zero-field cooling from an unmagnetized state. We propose that this is related to the newly formed interface between different magnetic phases during the initial magnetization process. The magnetic unidirectional anisotropy, which is the origin of the EB effect, can be created isothermally below the blocking temperature.