Pressure-Induced Increase of the Total Magnetic Moment in Ferrimagnetic Ni1.9375Mn1.5625Sn0.5 Martensite: A Quantum-Mechanical Study

0556885 - ÚFM 2023 RIV JP eng J - Journal Article
Friák, Martin - Mazalová, Martina - Turek, Ilja - Schneeweiss, Oldřich - Kaštil, Jiří - Kamarád, Jiří - Šob, Mojmír
Pressure-Induced Increase of the Total Magnetic Moment in Ferrimagnetic Ni1.9375Mn1.5625Sn0.5 Martensite: A Quantum-Mechanical Study.
Materials Transactions. Roč. 63, č. 4 (2022), s. 430-435. ISSN 1345-9678. E-ISSN 1347-5320
R&D Projects: GA ČR(CZ) GA20-16130S
Institutional support: RVO:68081723 ; RVO:68378271
Keywords : transport-properties * heusler alloy * curie-temperature * phase-transitions * crystal-structure * field * ni1.92mn1.56sn0.52 * transformations * ni2mnsn * Ni-Mn-Sn * magnetism * pressure * disorder * martensite * quantum-mechanical * stability * phonons
OECD category: Condensed matter physics (including formerly solid state physics, supercond.); Condensed matter physics (including formerly solid state physics, supercond.) (FZU-D)
Impact factor: 1.2, year: 2022
Method of publishing: Open access
https://www.jstage.jst.go.jp/article/matertrans/63/4/63_MT-MA2022006/_article

We have performed an ab initio study of disordered ferrimagnetic Ni1.9375Mn1.5625Sn0.5 martensite. Employing the supercell approach combined with the special quasi-random structure concept for modeling of disordered states we have determined thermodynamic, magnetic, structural, elastic and vibrational properties of the studied material. Its atomic and magnetic configuration is found to exhibit a pressure-induced increase of the total magnetic moment, i.e. the total magnetic moment increases with decreasing volume. This peculiar trend is revealed despite of the fact that the magnitudes of local magnetic moments of atoms decrease (or stay constant) with decreasing volume. The origin of the identified phenomena may be related to (i) the ferrimagnetic nature of the magnetic state when the parallel and antiparallel magnetic moments nearly compensate each other and (ii) chemical disorder that leads to different local atomic environments and, consequently, also to different local magnetic moments and their different response to hydrostatic pressures (the antiparallel moments are more sensitive). The studied state is mechanically and dynamically stable (no imaginary-frequency phonons) but, regarding its thermodynamic stability, it is an excited state.
Permanent Link: http://hdl.handle.net/11104/0331005