Physico-chemical nanomaterials science

Magnetoresistance and magnetic properties high-entropy film alloys with FCC lattice

Vorobiov S.I.1,2, Protsenko S.I.1, Panchal C.J.3, 
Оdnodvorets L.V.1, Poduremne D.V.1, Protsenko I.Yu.1

1 Electronic, General and Applied Physic Department, Sumy State University, Rymskyi-Korsakov Street, 2, Sumy-40007, Ukraine. 
E-mail: i.protsenko@aph.sumdu.edu.ua 

2 Technical University of Košice, Letná 9, 042 00 Košice, Slovak Republic.

3 Applied Physic Department, M.S. University of Baroda, Post Box 51, Vadodara, Kalabhavan, 390001, India.

The crystalline structure, mechanical and magnetic properties of a new class of materials – high-entropy alloys (HEA) (see, for example, [1]) in the form of bulk samples based on ferromagnetic (Fe, Ni, Co), fcc (Al, Cu etc.), bcc (Cr, V) or hpc (Hf, Zr, Ti) metals investigated in recent years. HEA is classified according to their structure. 
The research results of magnetoresistive (magnetoresistance) and magnetic (magnetization) properties of high-entropy film alloys based on Cu, Cr, Ni, Fe and Co with total thickness up to 100 nm are presented. Diffraction studies indicate that the base fcc phase is formed on the basis Cu (a = 0.360 – 0.365 nm).
Measurement of the magnetic resistivity (MR) in three geometries of mutual orientation of the current and magnetic field induction (parallel, transverse and perpendicular) indicates the realization of the giant magnetoresistance effect with an amplitude of 0.3 – 0.5%. The analysis shows that the realization of this effect occurs as a result of spin-dependent scattering of electrons on magnetic quasigranules that are observed by electron-microscopically method. The results of the field (induction B = 0 – 5 T) and temperature (interval 2 – 400 K) dependences of magnetization for high-entropy films of thickness up to 50 nm are presented.

1.	Yeh J.W., Chen S.K., Lin S.J., Gan J.-Y., Chin T.-S., Shun T.-T., Tsau C.-H., Chang S.-Y. Nanostructured high‐entropy alloys with multiple principal elements: novel alloy design concepts and outcomes // Advanced Engineering Materials. – 2004. – 6(5). – Р. 1.