Berlin 2015 – wissenschaftliches Programm
TT 71.42: Poster
Mittwoch, 18. März 2015, 15:00–18:00, Poster B
Possibility of a two-dimensional spin liquid in CePdAl induced by partial geometric frustration? — •V. Fritsch1,2, K. Grube2, W. Kittler2, C. Taubenheim2, Z. Huesges3, S. Lucas3, E. Green4, O. Stockert3, and H. v. Löhneysen2 — 1Universität Augsburg, Institut für Physik, Experimentalphysik VI, Germany — 2Karlsruher Institut für Technologie, Germany — 3Max-Planck-Institut für chemische Physik fester Stoffe, Dresden, Germany — 4Hochfeldzentrum Dresden-Rossendorf, Germany
CePdAl crystallizes in the hexagonal ZrNiAl structure, where the magnetic ions form a distorted kagomé lattice. At TN = 2.7 K the onset of antiferromagnetic (AF) order is observed. Neutron scattering experiments  revealed a partial frustration in the distorted kagomé planes of this structure: two-thirds of the Ce moments form ferromagnetic chains, which are antiferromagnetically coupled, the remaining third do not participate in any long-range order. Along the c-axis the magnetic moments exhibit an amplitude modulation. Accordingly, the kagomé planes are stacked on top of each other, resulting in corrugated AF planes parallel to the c-axis formed by the ordered magnetic moments, which are separated by the frustrated moments . It is an intriguing and yet unresolved question if this third of frustrated moments forms a spin liquid state in CePdAl. Based on measurements of specific heat, thermal expansion, magnetization and electrical resistivity we want to discuss this possibility.
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 V. Fritsch et al., Phys. Rev. B 89, 054416 (2014).