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Single-ion anisotropy in the gadolinium pyrochlores studied by an electron paramagnetic resonance

V. N. Glazkov·M. E. Zhitomirsky·A. I. Smirnov·H. -A. Krug von Nidda·A. Loidl·C. Marin·J. -P. Sanchez
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Abstract

The electron paramagnetic resonance is used to measure the single-ion anisotropy of Gd3+ ions in the pyrochlore structure of (Y{1-x}Gdx)2Ti2O7. A rather strong easy-plane type anisotropy is found. The anisotropy constant D is comparable to the exchange integral J in the prototype Gd2Ti2O7, D~0.75J and exceeds the dipolar energy scale. Physical implications of an easy-plane anisotropy for a pyrochlore antiferromagnet are considered. We calculate the magnetization curves at T=0 and discuss phase transitions in magnetic field.

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V. N. Glazkov, M. E. Zhitomirsky, A. I. Smirnov, H. -A. Krug von Nidda, A. Loidl, C. Marin, J. -P. Sanchez. 2005-07-18. Single-ion anisotropy in the gadolinium pyrochlores studied by an electron paramagnetic resonance. https://doi.org/10.1103/physrevb.72.020409

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