Data Storage: Review of Heusler Compounds

Abstract

In the recent decade, the family of Heusler compounds has attracted tremendous scientific and technological interest in the field of spintronics. This is essentially due to their exceptional magnetic properties, which qualify them as promising functional materials in various data-storage devices, such as giant-magnetoresistance spin valves, magnetic tunnel junctions, and spin-transfer torque devices. In this article, we provide a comprehensive review on the applications of the Heusler family in magnetic data storage. In addition to their important roles in the performance improvement of these devices, we also try to point out the challenges as well as possible solutions, of the current Heusler-based devices. We hope that this review would spark further investigation efforts into efficient incorporation of this eminent family of materials into data storage applications by fully arousing their intrinsic potential.

Half-metallic magnetism in Ti3Co5-xFexB2

“…Note that the combination of half-metallicity and perpendicular magnetic anisotropy in Ti 3 CoFe 4 B 2 is favorable for spintronics applications. 27 …”

Ab initio studies of Co2FeAl1−xSix Heusler alloys

“…For that composition, calculations predict that the Fermi level is located in the middle of the band gap of the minority band. Such position of the Fermi level enhances the thermal stability of the half-metallicity because reduces the sensitivity to thermal fluctuation effects [10].…”

Symmetry-dependent electron-electron interaction in coherent tunnel junctions resolved by measurements of zero-bias anomaly

“…In recent years, half metals which have full SP (P = 1) according to band calculations have drawn a lot of attention, especially the Heusler alloys [10]. Theoretically, with P = 1, the MR ratio can be infinity.…”

“…However, it is found thateven * weijian6791@pku.edu.cn † jiafengfeng@iphy.ac.cn for the half-metal full-Heusler Co 2 FeAl 0.5 Si 0.5 alloys, the MR ratio is not ideal when the quality of the tunneling barrier or the matching between the tunneling barrier and the electrodes is not perfect [11], while an excellent MR ratio is achieved when the matching is good [12]. Thus coherent tunneling is an indispensable factor to get a high MR ratio [10]. While the SP can be directly observed by in situ spin-resolved photoemission spectroscopy [13], there seems no reliable way to verify the coherent tunneling feature.…”