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Field-Driven Transitions in the Dipolar Pyrochlore Antiferromagnet Gd$_2$Ti$_2$O$_7$

Olivier Cepas·B. Sriram Shastry
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Abstract

We present a mean-field theory for magnetic field driven transitions in dipolar coupled gadolinium titanate Gd$_2$Ti$_2$O$_7$ pyrochlore system. Low temperature neutron scattering yields a phase that can be regarded as a 8 sublattice antiferromagnet, in which long-ranged ordered moments and fluctuating moments coexist. Our theory gives parameter regions where such a phase is realized, and predicts several other phases, with transitions amongst them driven by magnetic field as well as temperature. We find several instances of {\em local} disorder parameters describing the transitions.

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Olivier Cepas, B. Sriram Shastry. 2004-03-03. Field-Driven Transitions in the Dipolar Pyrochlore Antiferromagnet Gd$_2$Ti$_2$O$_7$. https://doi.org/10.1103/physrevb.69.184402

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