skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Exploring the microscopic origin of exchange bias with photoelectron emission microscopy (invited)

Journal Article · · Journal of Applied Physics
DOI:https://doi.org/10.1063/1.1358828· OSTI ID:40204025

It is well known that magnetic exchange coupling across the ferromagnet{endash}antiferromagnet interface results in an unidirectional magnetic anisotropy of the ferromagnetic layer, called exchange bias. Despite large experimental and theoretical efforts, the origin of exchange bias is still controversial, mainly because detection of the interfacial magnetic structure is difficult. We have applied photoelectron emission microscopy (PEEM) on several ferromagnet{endash}antiferromagnet thin-film structures and microscopically imaged the ferromagnetic and the antiferromagnetic structure with high spatial resolution. Taking advantage of the surface sensitivity and elemental specificity of PEEM, the magnetic configuration and critical properties such as the Neel temperature were determined on LaFeO{sub 3} and NiO thin films and single crystals. On samples coated with a ferromagnetic layer, we microscopically observe exchange coupling across the interface, causing a clear correspondence of the domain structures in the adjacent ferromagnet and antiferromagnet. Field dependent measurements reveal a strong uniaxial anisotropy in individual ferromagnetic domains. A local exchange bias was observed even in not explicitly field-annealed samples, caused by interfacial uncompensated magnetic spins. These experiments provide highly desired information on the relative orientation of electron spins at the interface between ferromagnets and antiferromagnets. {copyright} 2001 American Institute of Physics.

Sponsoring Organization:
(US)
OSTI ID:
40204025
Journal Information:
Journal of Applied Physics, Vol. 89, Issue 11; Other Information: DOI: 10.1063/1.1358828; Othernumber: JAPIAU000089000011007266000001; 373111MMM; PBD: 1 Jun 2001; ISSN 0021-8979
Publisher:
The American Physical Society
Country of Publication:
United States
Language:
English