Giant spontaneous exchange bias in an antiperovskite structure driven by a canted triangular magnetic structure. Issue 2 (31st October 2018)

• Record Type: Journal Article
• Authors: Ding, Lei; Chu, Lihua; Manuel, Pascal; Orlandi, Fabio; Li, Meicheng; Guo, Yanjiao; Liu, Zhuohai
• Is Part Of: Materials horizons. Volume 6:Issue 2(2019)
• Page Start: 318
• Page End: 325
• Publication Date: 2018-10-31
• Subjects: Materials -- Research -- Periodicals; 543.0284
• DOI: 10.1039/c8mh00019k
• Languages: English
• ISSNs: 2051-6347

Abstract

Abstract : Schematic exchange bias and a vertical magnetization shift, originating from the mGM4 + magnetic structure in antiperovskites. Abstract : Exchange bias (EB) effect, generally observed in systems consisting of ferromagnetic and antiferromagnetic layers after a cooling procedure in a high magnetic field, is highly desirable for technological applications ranging from spintronics to magnetic recording. Achieving a giant EB effect near room temperature in a small cooling field is thus an on-going technologically relevant challenge for the materials science community. In this work, we present the experimental realization of such a fundamental goal by demonstrating the existence of giant EB after a zero field cooled (ZFC) procedure in antiperovskite Mn3.5 Co0.5 N below 256 K. We found that it exhibits an EB field of −0.28 T at 50 K after a ZFC procedure accompanied by a large vertical magnetization shift (VMS). Interestingly, this EB field can be elevated up to −1.2 T after a cooling procedure with a small applied field of just 500 Oe. Mn3.5 Co0.5 N represents the first intermetallic material showing a strong correlation between EB and VMS. We attribute the observed EB effect to a new canted triangular magnetic structure in antiperovskites determined by a neutron diffraction experiment. Finally, we discuss the striking effect of Co substitution on the physical properties of antiperovskite materials and put forward a new strategy for the antiperovskite lattice to exploit new single phase materials showing large EB effect at room temperature.