Absence of long-range magnetic ordering in the pyrochlore compound Er2Sn2O7.

Department of Chemistry, University of Winnipeg, Winnipeg, MB, R3B 2E9, Canada.
Journal of Physics Condensed Matter (Impact Factor: 2.22). 09/2011; 23(38):382201. DOI: 10.1088/0953-8984/23/38/382201
Source: PubMed

ABSTRACT The low temperature behaviour of powder Er2Sn2O7 samples has been studied by magnetic susceptibility, heat capacity, and neutron scattering experiments. We report here the absence of magnetic ordering down to 100 mK. Anomalies in the heat capacity can be accounted for through an analysis of the crystal field spectrum observed by inelastic neutron scattering spectroscopy. These new measurements on Er2Sn2O7 suggest a new lower bound for the frustration index of f = |Θ(CW)|/T(N) = 14/0.1 = 140, placing this compound into a highly frustrated regime.

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