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تسجيل مستخدم جديدCoexisting Magnetic Order and Cooperative Paramagnetism in the Stuffed Pyrochlore Tb_{2+x}Ti_{2-2x}Nb_xO_7
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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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Specific heat, elastic neutron scattering, and muon spin rotation ($mu$SR) experiments have been carried out on a well-characterized sample of stuffed (Pr-rich) Pr$_{2+x}$Ir$_{2-x}$O$_{7-delta}$. Elastic neutron scattering shows the onset of long-ran
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