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arXiv · 1001.2021

Coexisting Magnetic Order and Cooperative Paramagnetism in the Stuffed Pyrochlore Tb_{2+x}Ti_{2-2x}Nb_xO_7

B. G. Ueland·J. S. Gardner·A. J. Williams·M. L. Dahlberg·J. G. Kim·Y. Qiu·J. R. D. Copley·P. Schiffer·R. J. Cava
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Abstract

Neutron scattering and magnetization measurements have been performed on the stuffed pyrochlore system Tb2+xTi2-2xNbxO7. We find that despite the introduction of chemical disorder and increasingly antiferromagnetic interactions, a spin glass transition does not occur for T >= 1.5 K and cooperative paramagnetic behavior exists for all x. For x = 1, Tb3NbO7, an antiferromagnetically ordered state coexisting with cooperative paramagnetic behavior is seen without applying any external fields or pressure, a situation advantageous for studying this cooperative behavior.

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B. G. Ueland, J. S. Gardner, A. J. Williams, M. L. Dahlberg, J. G. Kim, Y. Qiu, J. R. D. Copley, P. Schiffer, R. J. Cava. 2010-01-12. Coexisting Magnetic Order and Cooperative Paramagnetism in the Stuffed Pyrochlore Tb_{2+x}Ti_{2-2x}Nb_xO_7. https://doi.org/10.1103/physrevb.81.060408

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