Exchange coupling in GdM compounds

https://doi.org/10.1016/S0925-8388(96)02431-0Get rights and content

Abstract

The magnetic susceptibility of ferromagnetic GdM alloys (M = Cu1−x Gax Mg, Zn) has been investigated under helium gas pressure for temperatures above Tc. The evaluated pressure derivatives of the paramagnetic Curie temperature, d ln ΘdP. appeared to be remarkably different for isovalent GdMg and GdZn compounds (−11.2 Mbar 1 and −0.1 Mbar 1 respectively). Analysis of the obtained d ln ΘdP values for GdCu1−xGax alloys and results of ab initio electronic structure calculations have revealed the essential role of 5d electrons as the mediators of exchange coupling in ferromagnetic GdM compounds. The pressure derivatives of Tc were calculated in the frameworks of modern mean-field theories by using volume-dependent band and exchange parameters, and including spin fluctuations effects. As a result, good agreement is found with the experimental values of d ln ΘdP.

References (26)

  • J.J.M. Franse et al.
  • G.E. Grechnev et al.

    J. Alloys Compd.

    (1995)
  • M.S.S. Brooks et al.

    J. Magn. Magn. Mater.

    (1992)
  • M. Divis et al.

    Physica B

    (1993)
  • M.M. Amado et al.

    J. Magn. Magn. Mater.

    (1996)
  • K.H.J. Buschow
  • I.A. Campbell

    J. Phys. F

    (1972)
  • E. Belorizky et al.

    Europhys. Lett.

    (1988)
  • M.S.S. Brooks et al.

    J. Phys.: Condens. Matter

    (1991)
  • M. Liebs et al.

    Phys. Rev. B

    (1992)
  • A.S. Panfilov

    Phys. Tech. High Pressure

    (1992)
  • T. Hiraoka

    J. Phys. Soc. Jpn.

    (1974)
  • J.C.M. van Dongen et al.

    Phys. Rev. B

    (1983)
  • Cited by (20)

    • Magnetic properties of Gd intermetallics

      2018, Journal of Magnetism and Magnetic Materials
    • The structural, electronic, elastic, vibration and thermodynamic properties of GdMg

      2013, Solid State Sciences
      Citation Excerpt :

      The cycling durability and degradation mechanism of GdMg metal films (with Pd topcoat) have been studied with electrochemical switching in a 1 M KOH solution by Janner et al. [7]. The magnetic susceptibility of ferromagnetic GdM alloys (M = Cu, Ga, Mg, Zn) have been investigated under helium gas by Buschow et al. [8]. The comprehensive investigation to cohesive properties of 344 inter metallic compounds in 17 Mg–RE (RE = Sc, Y, and Lanthanide elements) binary system has been carried out systematically in the framework of density functional theory (DFT) type first-principles with the generalized gradient approximation (GGA) by Tao et al. [9].

    • Effects of pressure on magnetic properties of gadolinium

      2012, Physica B: Condensed Matter
      Citation Excerpt :

      In the ground state both metals possess the hexagonal closed-packed (HCP) structure. For these calculations we employed a full-potential all-electron relativistic linear muffin-tin orbital method (FP-LMTO, code RSPt [29–31]), and also the LMTO method in atomic sphere approximation (LMTO-ASA code, see Refs. [32–35]). The exchange-correlation potential was treated within the local spin density approximation (LSDA) of the density functional theory (DFT) [36].

    • Hydrogen-induced magnetic and structural transformations of GdCu

      2009, Journal of Magnetism and Magnetic Materials
    • Electronic structure and magnetic properties of GdM<inf>2</inf> compounds

      2003, Journal of Magnetism and Magnetic Materials
    View all citing articles on Scopus
    View full text