Antiferromagnet-ferromagnet transition in La₁–xSrxMn₀.₅Ni₀.₅O₃ (0 ≤ x ≤ 0.2) ceramics

• Published in: Физика низких температур
• Date: 2017
• Main Authors: Troyanchuk, I.O., Karpinsky, D.V., Bushinsky, M.V., Sirenko, V.A., Sikolenko, V.V., Franz, A.
• Format: Article
• Language: English
• Published: Фізико-технічний інститут низьких температур ім. Б.І. Вєркіна НАН України 2017
• Subjects: Low dimensionality and inhomogeneity effects in quantum matter
• Online Access: https://nasplib.isofts.kiev.ua/handle/123456789/175140
• Journal Title: Digital Library of Periodicals of National Academy of Sciences of Ukraine
• Cite this: Antiferromagnet-ferromagnet transition in La₁–xSrxMn₀.₅Ni₀.₅O₃ (0 ≤ x ≤ 0.2) ceramics / I.O. Troyanchuk, D.V. Karpinsky, M.V. Bushinsky, V.A. Sirenko, V.V. Sikolenko, A. Franz // Физика низких температур. — 2017. — Т. 43, № 8. — С. 1219-1223. — Бібліогр.: 13 назв. — англ.

Ceramics samples of La₁–xSrxMn₀.₅Ni₀.₅O₃ (0 ≤ x ≤ 0.2) with perovskite structure have been studied by neutron diffraction method, magnetometry and magnetoresistance measurements. Structural data testify a partial order of the Ni and Mn ions in all the compounds in spite of chemical substitution of the La³⁺ ions by Sr²⁺ ones and an increase of the oxidation state of the Ni ions from 2+ towards to 3+ one. Magnetic structure of the compounds changes from ferromagnetic one (specific for the compound with x = 0) to antiferromagnetic (compounds with x ≥ 0.1) while the temperature of a transition into paramagnetic state remains about 270 K for all the samples. Magnetoresistance gradually decreases with temperature increase and strontium content. The results are discussed assuming nearly equal ferromagnetic and antiferromagnetic components of the superexchange interaction Ni²⁺–O–Mn⁴⁺ while the interaction between Ni³⁺ and Mn⁴ ions is considered to be strongly antiferromagnetic.