Advances in Engineering Advances in Engineering features breaking research judged by Advances in Engineering advisory team to be of key importance in the Engineering field. Papers are selected from over 10,000 published each week from most peer reviewed journals.
Zhu L, Nie S, Meng K, Pan D, Zhao J, Zheng H.
Adv Mater. 2012 Aug 28;24(33):4547-51.
State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, P.O. BOX 912, Beijing 100083, China.
Abstract
A new kind of multifunctional L1(0) -Mn(1.5)Ga film is demonstrated for the first time. These MBE-grown epitaxial films exhibit pronounced magnetic properties at room temperature, including ultrahigh perpendicular coercivity up to 42.8 kOe, giant perpendicular magnetic anisotropy with a maximum of 21.7 Merg/cm(3) and large magnetic energy products up to 2.60 MGOe, which allow various applications in ultrahigh density recording, spintronics, and permanent magnets.
Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Additional Information:
Magnetic materials with high coercivity, perpendicular magnetic anisotropy (PMA) and magnetic energy product have great application potential in ultrahigh-density perpendicular magnetic recording media, high-performance permanent magnets and ferromagnetic electrodes of spintronic devices with high magnetic-noise immunity and thermal stability. Moreover, many interesting physical phenomena like efficient spin injection into semiconductors from ferromagnetic contact in remanence, giant anomalous Hall effect, and long-lived ultrafast spin procession have been observed in materials with large PMA. Among the various PMA materials, noble-metal-based L10-ordered FePt, FePd and CoPt granular films may exhibit high Hc and PMA. However, the difficulty in attaining (001)-orientation, indispensable high-temperature (>500 oC) annealing process to form L10 ordering, and large surface roughness due to their granular textures greatly limit their applications in both magnetic storage and spintronics. On the other hand, rare-earth magnets provide the backbone of many products including computers, mobile phones, electric cars and wind-powered generators. However, because of both the increasingly limited availability and high costs of mining and processing of rare-earth elements, new kind of magnetic materials free of rare-earth elements are still urgently needed to replace the expensive rare-earth magnets widely used today.
Alloys of MnxGa with perpendicular anisotropy have gained increasing attention for possible applications in ultrahigh-density magnetic recording media, permanent magnets and spintronics (L. Zhu and J. Zhao*, Appl. Phys. A, DOI: 10.1007/s00339-013-7608-4 (2013)). The magnetic properties were also observed to be effectively tailored by many methods, such as by controlling composition and postannealing (Zhu et al, arXiv: 1210. 2062 (2012)).
