Magnetic order in YbMn2Si2 - Neutron scattering investigation

Authors

Stewart J. Campbell, University Of New South WalesFollow
M Hofmann, Technical University Of Munich
R A. Mole, University Of New South Wales
K Prokes, Helmholz Zentrum Berlin
D Wallacher, Helmholz Zentrum Berlin
Jianli Wang, University of WollongongFollow

RIS ID

82076

Publication Details

Campbell, S. J., Hofmann, M., Mole, R. A., Prokes, K., Wallacher, D. and Wang, J. (2013). Magnetic order in YbMn2Si2 - Neutron scattering investigation. Journal of the Korean Physical Society, 63 (3), 314-319.

Abstract

Several mechanisms have been proposed to account for the structural and magnetic behaviour of the rare earth intermetallic compound YbMn2Si2 below the transition that occurs around ∼30 K. We have carried out detailed neutron diffraction measurements over the temperature range ∼0.3-52 K and confirm both an antiferromagnetic structure with ferromagnetic Mn (001) planes coupled antiferromagnetically along the c-axis above ∼30 K and the absence of ordering of the Yb sublattice down to 0.3 K. The decrease in intensity of the (111) reflection around ∼30 K together with the appearance of satellite reflections of propagation vector k = 001/2 confirm that the magnetic unit cell doubles along the c axis below T N2. The resultant molecular field acting on half of the ions below ∼30 K removes the degeneracy of the Kramers doublets of the Yb3+ ions and accounts for the additional excitations observed below ∼30 K compared with the inelastic neutron scattering above ∼30 K.