Magnetic order in the double pyrochlore Tb2Ru2O7

• Published in: Journal of physics. Condensed matter 2010-02, Vol.22 (7), p.076003-076003
• Main Authors: Chang, L J, Prager, M, Perßon, J, Walter, J, Jansen, E, Chen, Y Y, Gardner, J S
• Format: Article
• Language: English
• Subjects: Condensed matter; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Critical-point effects, specific heats, short-range order; Direct current; Entropy; Exact sciences and technology; Magnetic permeability; Magnetic properties and materials; Magnetically ordered materials: other intrinsic properties; Magnetocaloric effect, magnetic cooling; Neutron scattering; Physics; Pyrochlores; Spin arrangements in magnetically ordered materials (including neutron and spin-polarized electron studies, synchrotron-source x-ray scattering, etc.); Spin liquid; Static properties (order parameter, static susceptibility, heat capacities, critical exponents, etc.); Terbium
• ISSN: 0953-8984; 1361-648X
• DOI: 10.1088/0953-8984/22/7/076003

Polycrystalline Tb2Ru2O7 has been studied using dc susceptibility, specific heat and neutron scattering techniques. The high temperature paramagnetic state is dominated by the single ion character of Tb3 + and very similar to that of the well-studied spin liquid Tb2Ti2O7. However, both the Ru4 + and Tb3 + sublattices order, at about 110 K and 3.5 K, respectively. Although the Tb sublattice does not fully order until 3.5 K, it is polarized in the presence of the internal field generated by the Ru4 + sublattice and possesses a significant moment at 7 K. Magnetic entropy measurements suggest that four levels exist in the first 30 K and inelastic neutron scattering investigations revealed two more levels at 10 and 14 meV. As the magnetic sublattices order, the excitations are perturbed from that measured in the paramagnetic state. These data are compared to data for other terbium based and double pyrochlores.