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arXiv · 2309.05493

Experimental realization of a high Curie temperature CoFeRuSn quaternary Heusler alloy for spintronic applications

Abstract

We synthesize CoFeRuSn equiatomic quaternary Heusler alloy using arc-melt technique and investigate its structural, magnetic and transport properties. The room temperature powder X-ray diffraction analysis reveals that CoFeRuSn crystallizes in cubic crystal structure with small amount of DO3 - disorder. The field dependence of magnetization shows non-zero but small hysteresis and saturation behavior up to room temperature, indicating soft ferromagnetic nature of CoFeRuSn. The magnetic moment estimated from the magnetization data is found to be 4.15 μB / f.u., which is slightly less than the expected Slater-Pauling rule. The deviation in the value of experimentally observed moment from the theoretical value might be due to small disorder in the crystal. The low temperature fit to electrical resistivity data show absence of quadratic temperature dependence of resistivity, suggesting half-metallic behavior of CoFeRuSn. The high Curie temperature and possible half-metallic behavior of CoFeRuSn make it a highly promising candidate for room temperature spintronic applications.

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Ravinder Kumar, Sachin Gupta. 2023-09-11. Experimental realization of a high Curie temperature CoFeRuSn quaternary Heusler alloy for spintronic applications. https://doi.org/10.1063/5.0178437

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