Электронный каталог

Статья

Tsvyashchenko, A.V.
Observation of Helimagnetism in New Chiral Crystal of Fe&sub(0.5)Rh&sub(0.5)Si / A.V.Tsvyashchenko, N.M.Chtchelkatchev, [a.o.]. – Text : electronic // Journal of Alloys and Compounds. – 2026. – Vol. 1054. – P. 186373. – URL: https://doi.org/10.1016/j.jallcom.2026.186373. – Bibliogr.: 101.

A single-phase stoichiometric compound of the composition Fe&sub(0.5)Rh&sub(0.5)Si (FeSi structural type) was obtained, exhibiting stability under ambient pressure conditions. The magnetic, transport, and thermodynamic properties of the new compound were studied. Band structure calculations were also performed using density functional theory (DFT). Magnetization measurements revealed the emergence of helimagnetism with a magnetic ordering temperature of 𝑇&sub(𝐶) = 65.6 K and a spontaneous magnetic moment per Fe atom at 2 K is 0.48 *mB , which is smaller then the value 1.4 *mB one obtains in paramagnetic region. The hyperfine field on Fe nuclei in Fe&sub(0.5)Rh&sub(0.5)Si was determined to be &sup(57)𝒉&sub(𝑙𝑜𝑐) ≈ 63 kOe, which corresponds to the magnetic moment of 0.49 *mB per Fe atom. Furthermore, it was determined that magnetic entropy release in the 2–140 K temperature (𝑇 ) range corresponds to a magnetic moment of 1 *mB /Fe. A magnetic field - temperature (𝐻 − 𝑇 ) phase diagram was constructed from an analysis of the 𝑀(𝐻) magnetization curves, revealing a region below 𝑇&sub(𝐶) similar to the A phase observed in the 𝐻 − 𝑇 diagram for Fe&sub(0.5)Co&sub(0.5)Si. Despite the fact that Fe&sub(0.5)Rh&sub(0.5)Si is a highly disordered system, metallic resistance behavior is observed. Transverse magnetoresistance, defined as *D*r∕*r = [*r(𝑇&sub(0) , 𝐻) − *r(𝑇&sub(0) , 𝐻 = 0)]∕*r(𝑇&sub(0) , 𝐻 = 0), was also measured in the range 1.7 – 120 K. The results of DFT calculations showed that at 0 K, the ground state is ferromagnetic. The band structure of spin-up Fe&sub(0.5)Rh&sub(0.5)Si (B20) was found to exhibit a triple band intersection (Weyl node) at the 𝛤 point near the Fermi level, which was not observed for Fe&sub(0.5)Co&sub(0.5)Si. Fermi surfaces were constructed for the spin-up and spin-down band structures. It was shown that the properties of this compound depend significantly on the preparation method and its stoichiometric composition. Thus, Fe&sub(0.5)Rh&sub(0.5)Si is a newly identified member of the B20 family of chiral crystals.



Спец.(статьи,препринты) = С 36 - Физика твердого тела$
Спец.(статьи,препринты) = С 326.3 - Ферми-системы. Спиновые системы
ОИЯИ = ОИЯИ (JINR)2026