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Magnetic phase diagram of the antiferromagnetic pyrochlore Gd2Ti2O7

O. A. Petrenko·M. R. Lees·G. Balakrishnan·D. McK. Paul
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Abstract

Gd2Ti2O7 is a highly frustrated antiferromagnet on a pyrochlore lattice, where apart from the Heisenberg exchange the spins also interact via dipole-dipole forces. We report on low-temperature specific heat measurements performed on single crystals of Gd2Ti2O7 for three different directions of an applied magnetic field. The measurements reveal the strongly anisotropic behaviour of Gd2Ti2O7 in a magnetic field despite the apparent absence of a significant single-ion anisotropy for Gd3+. The H-T phase diagrams are constructed for H//111], H//[110] and H//[112]. The results indicate that further theoretical work beyond a simple mean-field model is required.

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O. A. Petrenko, M. R. Lees, G. Balakrishnan, D. McK. Paul. 2003-09-17. Magnetic phase diagram of the antiferromagnetic pyrochlore Gd2Ti2O7. https://doi.org/10.1103/physrevb.70.012402

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