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arXiv · 2105.05200

First-principles calculations and experimental studies on Co2FeGe Heusler alloy nanoparticles for spintronics applications

Aquil Ahmad·S. K. Srivastava·A. K. Das
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Abstract

Here, we report the synthesis and physical properties of Co2FeGe (CFG) Heusler alloy (HA) nanoparticles (NPs). The NPs of size 23 nm are prepared using the co-precipitation method. X-ray and selected area electron diffraction patterns have confirmed the cubic Heusler phase of the NPs with the A2-disorder. These NPs are soft ferromagnetic, and exhibit a high saturation magnetization (Ms) along with a very high Curie temperature (Tc) of 1060 K. The observed Tc value matches closely with the theoretically calculated one following a model provided by Wurmehl et al. [1]. The high Ms and Tc make the present system a potential candidate for magnetically activated nano-devices working at high temperatures. The near-integral value 5.9 mehoB/f.u. of Ms at low temperatures indicates that the half-metallic ferromagnetism is preserved even in the particles even on the 20 nm length scale. Additionally, we have facilitated the existing HA-NP preparation method, which can be used in synthesizing other HA-NPs. The first-principles density functional theory computations complement the experimental results.

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Aquil Ahmad, S. K. Srivastava, A. K. Das. 2021-05-11. First-principles calculations and experimental studies on Co2FeGe Heusler alloy nanoparticles for spintronics applications. https://doi.org/10.1016/j.jallcom.2021.160341

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