Effective spin-1/2 exchange interactions in Tb₂Ti₂O₇

الأصل · EN

We derive an effective spin-1/2 exchange model for non-Kramers Tb³⁺ states in the pyrochlore Tb₂Ti₂O₇. 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 Tb₂Ti₂O₇ is described by a quantum spin ice Hamiltonian.