Field-driven phase transitions generally arise from competition between Zeeman energy and exchange or crystal-field anisotropy. Here we present the phase diagram of a frustrated pyrochlore magnet Gd2Ti2O7, where crystal field splitting is small compared to the dipolar energy. We find good agreement between zero-temperature critical fields and those obtained from a mean-field model. Here, dipolar interactions couple real-space and spin-space, so the transitions in Gd2Ti2O7 arise from field-induced "cooperative anisotropy" reflecting the broken spatial symmetries of the pyrochlore lattice.
@article{arxiv.cond-mat/0112022,
title = {Multiple Field-Induced Phase Transitions in a Geometrically-Frustrated Dipolar Magnet - Gd2Ti2O7},
author = {A. P. Ramirez and B. S. Shastry and A. Hayashi and J. J. Krajewski and D. A. Huse and R. J. Cava},
journal= {arXiv preprint arXiv:cond-mat/0112022},
year = {2016}
}
Comments
10pages,5figures: pdf file attached PACS 75.30.Kz, 75.50.Ee, 75.10.-b