Summary: Physica B 403 (2008) 14111413
Yb2Pt2Pb: A new quasi-two-dimensional antiferromagnet
M.S. Kima,b,Ã, M.C. Bennettb
, M.C. Aronsona,b,c
Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY 11973 5000, USA
Department of Physics, University of Michigan, Ann Arbor, MI 48109 1120, USA
Department of Physics and Astronomy, State University of New York, Stony Brook, NY 11794 3800, USA
We have synthesized single-crystals of Yb2Pt2Pb, which crystallize in the tetragonal U2Pt2Sn-type structure. The magnetic
susceptibility w is highly anisotropic. The wh1 0 0i for Bkh1 0 0i is 30 times larger than wh0 0 1i for Bkh0 0 1i at the lowest temperatures. Both
1=wðTÞ and MðBÞ of Yb2Pt2Pb are dominated by the CEF effect. The 1=wh1 0 0i above 150 K is well described by the CurieWeiss law with
y ¼ 34 K and meff ¼ 4:19mB, indicating well-localized Yb3þ
ions at high temperatures. A broad maximum in w is found around 3 K, just
above antiferromagnetic transition temperature of 2 K. This suggests an important role for fluctuations in this system, due to reduced
dimensionality or perhaps geometric frustration.
r 2007 Elsevier B.V. All rights reserved.
PACS: 75.30.Gw; 75.30.Àm; 75.30.Kz