University of Wollongong
Browse

Pressure induced magneto-structural phase transitions in layered RMn2X2 compounds (invited)

Download (2.14 MB)
journal contribution
posted on 2024-11-15, 14:06 authored by Shane Kennedy, Jianli WangJianli Wang, Stewart Campbell, Michael Hofmann, Shi DouShi Dou
We have studied a range of pseudo-ternaries derived from the parent compound PrMn2 Ge 2, substituting for each constituent element with a smaller one to contract the lattice. This enables us to observe the magneto-elastic transitions that occur as the Mn-Mn nearest neighbour distance is reduced and to assess the role of Pr on the magnetism. Here, we report on the PrMn2 Ge 2−xSix, Pr1−xYxMn2 Ge 2, and PrMn2−xFex Ge 2 systems. The pressure produced by chemical substitution in these pseudo-ternaries is inherently non-uniform, with local pressure variations dependent on the local atomic distribution. We find that concentrated chemical substitution on the R or X site (e.g., in Pr 0. 5 Y 0. 5 Mn 2 Ge 2 and PrMn 2 Ge 0. 8 Si 1. 2) can produce a separation into two distinct magnetic phases, canted ferromagnetic and canted antiferromagnetic, with a commensurate phase gap in the crystalline lattice. This phase gap is a consequence of the combination of phase separation and spontaneous magnetostriction, which is positive on transition to the canted ferromagnetic phase and negative on transition to the canted antiferromagnetic phase. Our results show that co-existence of canted ferromagnetic and antiferromagnetic phases depends on chemical pressure from the rare earth and metalloid sites, on local lattice strain distributions and on applied magnetic field. We demonstrate that the effects of chemical pressure bear close resemblance to those of mechanical pressure on the parent compound.

History

Citation

Kennedy, S., Wang, J., Campbell, S., Hofmann, M. & Dou, S. (2014). Pressure induced magneto-structural phase transitions in layered RMn2X2 compounds (invited). Journal of Applied Physics, 115 (17), 172617-1-172617-6.

Journal title

Journal of Applied Physics

Volume

115

Issue

17

Language

English

RIS ID

90958

Usage metrics

    Categories

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC