1. |
- Kan, Erjun, et al.
(author)
-
Two-Dimensional Hexagonal Transition-Metal Oxide for Spintronics
- 2013
-
In: The Journal of Physical Chemistry Letters. - : American Chemical Society (ACS). - 1948-7185. ; 4:7, s. 1120-1125
-
Journal article (peer-reviewed)abstract
- Two-dimensional materials have been the hot subject of studies due to their great potential in applications. However, their applications in spintronics have been blocked by the difficulty in producing ordered spin structures in 2D structures. Here we demonstrated that the ultrathin films of recently experimentally realized wurtzite MnO can automatically transform into a stable graphitic structure with ordered spin arrangement via density functional calculation, and the stability of graphitic structure can be enhanced by external strain. Moreover, the antiferromagnetic ordering of graphitic MnO single layer can be switched into half-metallic ferromagnetism by small hole-doping, and the estimated Curie temperature is higher than 300 K. Thus, our results highlight a promising way toward 2D magnetic materials.
|
|
2. |
- Li, Zhuo, et al.
(author)
-
Atomic Structure and Electron Magnetic Circular Dichroism of Individual Rock Salt Structure Antiphase Boundaries in Spinel Ferrites
- 2021
-
In: Advanced Functional Materials. - : John Wiley & Sons. - 1616-301X .- 1616-3028. ; 31:21
-
Journal article (peer-reviewed)abstract
- Spinel ferrites are an important class of materials, whose magnetic properties are of interest for industrial applications. The antiphase boundaries (APBs) that are commonly observed in spinel ferrite films can hinder their applications in spintronic devices and sensors, as a result of their influence on magnetic degradation and magnetoresistance of the materials. However, it is challenging to correlate magnetic properties with atomic structure in individual APBs due to the limited spatial resolution of most magnetic imaging techniques. Here, aberration-corrected scanning transmission electron microscopy and electron energy-loss magnetic chiral dichroism are used to measure the atomic structure and electron magnetic circular dichroism (EMCD) of a single APB in NiFe2O4 that takes the form of a rock salt structure interlayer and is associated with a crystal translation of (1/4)a[011]. First principles density functional theory calculations are used to confirm that this specific APB introduces antiferromagnetic coupling and a significant decrease in the magnitude of the magnetic moments, which is consistent with an observed decrease in EMCD signal at the APB. The results provide new insight into the physical origins of magnetic coupling at an individual defect on the atomic scale.
|
|