We report the synthesis and basic properties of single crystals of a new binary compound, Yb3 Pt4. The Yb ions in this compound are fully trivalent, and heat capacity measurements show that the crystal field scheme involves a doublet ground state, well separated from the excited states, which are fully occupied above ∼ 150 K. The heat capacity displays a large, weakly first order anomaly at 2.4 K, where a cusp is observed in the magnetic susceptibility signalling the onset of antiferromagnetic order. The entropy associated with this order is the full Rln2 of the doublet ground state, however, the magnetic susceptibility in the ordered phase is dominated by a large and temperature independent component below the Neel temperature. The heat capacity in the ordered state originates with ferromagnetic spin waves, giving evidence for the inherently local moment character of the ordered state. The electrical resistivity is unusually large, and becomes quadratic in temperature exactly at the Neel temperature. The absence of analogous Fermi liquid behavior in the heat capacity and the magnetic susceptibility implies that Yb3 Pt4 is a low electron density system, where the Fermi surface is further gapped by the onset of magnetic order.
|Number of pages||6|
|Journal||Journal of Magnetism and Magnetic Materials|
|State||Published - Jul 2009|
Bibliographical noteFunding Information:
The authors acknowledge useful conversations with C. Varma, Q. Si, J.W. Allen, P. Coleman, J. Kampf and P. Stephens. We are grateful to J. Chan and J. Millican for crystallographic consultations. Electron microscopy was carried out at the University of Michigan Electron Microbeam Analytical Laboratory (EMAL). Work at the University of Michigan and at Stony Brook University was supported by the National Science Foundation under Grant NSF-DMR-0405961.
- Binary intermetallic
- Fermi liquid
- Magnetic susceptibility
- Specific heat
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics