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Field Induced Order and Spin Waves in the Pyrochlore Antiferromagnet Tb2Ti2O7

K. C. Rule·J. P. C. Ruff·B. D. Gaulin·S. R. Dunsiger·J. S. Gardner·J. P. Clancy·M. J. Lewis·H. A. Dabkowska·I Mirebeau·P. Manuel·Y. Qiu·J. R. D. Copley
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Abstract

High resolution time-of-flight neutron scattering measurements on Tb2Ti2O7 reveal a rich low temperature phase diagram in the presence of a magnetic field applied along [110]. In zero field at T=0.4 K, terbium titanate is a highly correlated cooperative paramagnet with disordered spins residing on a pyrochlore lattice of corner-sharing tetrahedra. Application of a small field condenses much of the magnetic diffuse scattering, characteristic of the disordered spins, into a new Bragg peak characteristic of a polarized paramagnet. At higher fields, a magnetically ordered phase is induced, which supports spin wave excitations indicative of continuous, rather than Ising-like spin degrees of freedom.

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K. C. Rule, J. P. C. Ruff, B. D. Gaulin, S. R. Dunsiger, J. S. Gardner, J. P. Clancy, M. J. Lewis, H. A. Dabkowska, I Mirebeau, P. Manuel, Y. Qiu, J. R. D. Copley. 2006-01-31. Field Induced Order and Spin Waves in the Pyrochlore Antiferromagnet Tb2Ti2O7. https://doi.org/10.1103/physrevlett.96.177201

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