Surface antiferromagnetic domain imaging using low-energy unpolarized electrons

Abstract

We report on the surface antiferromagnetic (AFM) domain imaging of the prototype antiferromagnet NiO(100) using an electron-microscopy-based laboratory method. Coherently exchange-scattered electrons from the surface AFM lattice are utilized in a low-energy electron microscope to resolve the surface domain structure. Direct comparison with x-ray magnetic linear dichroism photoemission electron microscopy demonstrates a complimentary nature. High surface sensitivity combined with improved spatial resolution of this method enables studying of nanosized magnetic domains in NiO(100) thin films and their thickness-dependent evolution.

Tuning the Néel temperature in an antiferromagnet: the case of NixCo1−xO microstructures

“…However, the domains visible at the oxygen edge are different. This is a strong indication that dichroic contrast at Co and Ni edges is indeed of magnetic origin, since the cation edge dichroic images are sensitive to domains with different spin directions in addition to different ordering directions, while the anion edge is only sensitive to the latter 23,44 . The determination of the spin and ordering axis of each domain is beyond the scope of this manuscript and will be published elsewhere.…”

Angle-resolved X-ray photoemission electron microscopy

“…for determination of surface termination and stacking faults [28], or adsorption-site symmetry [29]. Recently, darkfield LEEM based on electron exchange scattering from magnetic lattices was successfully used to image antiferromagnetic domains in NiO [30].…”

Surface magnetism of NiO investigated by magnetic spectromicroscopies

“…2 contain common surface features, however, contrast pattern is completely different. The observed contrast in the AFM-LEEM image can be directly associated with the AFM T domain distribution at the surface 46 . This method is most surface sensitive due to much reduced probing depth (∼ 0.2-0.5 nm) of low energy electrons 50 .…”

“…3(b) also represent the similar situation. Hence the curved domains observed in Ni L 2 edge images originate due to AFM spin axes perturbed by induced surface strain or by crystal defects 44,51,46 . This can be considered as direct manifestation of the magnetoelastic nature of AFM domain structure 4,44 .…”

“…A new approach to image surface domains of NiO(100) utilizing observed exchange-scattered half-order spots in LEED pattern 45 is presented recently 46 . Temperature dependent intensity of half-order spots has also (a) A c c e p t e d M a n u s c r i p t surface is presented in Fig.…”