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arXiv · 1406.5991

Effective spin-1/2 exchange interactions in Tb$_2$Ti$_2$O$_7$

S. P. Mukherjee·S. H. Curnoe
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Abstract

We derive an effective spin-1/2 exchange model for non-Kramers Tb$^{3+}$ states in the pyrochlore Tb$_2$Ti$_2$O$_7$. The four anisotropic nearest-neighbour exchange constants, as well as next-neighbour exchange constants are derived for the effective model. This work goes beyond the independent tetrahedra model by considering all nearest-neighbour exchange paths on the pyrochlore lattice. Estimates of the exchange constants reveal that Tb$_2$Ti$_2$O$_7$ is described by a quantum spin ice Hamiltonian.

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S. P. Mukherjee, S. H. Curnoe. 2014-06-23. Effective spin-1/2 exchange interactions in Tb$_2$Ti$_2$O$_7$. https://doi.org/10.1103/physrevb.90.214404

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