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arXiv · 1203.6669

Magnetic Order in the Pyrochlore Iridates A2Ir2O7 (A = Y, Yb)

S. M. Disseler·Chetan Dhital·A. Amato·S. R. Giblin·Clarina de la Cruz·Stephen D. Wilson·M. J. Graf
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Abstract

We present results from muon spin relaxation/rotation, magnetization, neutron scattering and transport measurements on polycrystalline samples of the pyrochlore iridates Y2Ir2O7 (Y-227) and Yb2Ir2O7 (Yb-227). Well-defined spontaneous oscillations of the muon asymmetry are observed together with hysteretic behavior in magnetization below 130 K in Yb-227, indicative of commensurate long-range magnetic order. Similar oscillations are observed in Y-227 below 150 K; however the onset of hysteretic magnetization at T = 190 K indicates a transition to an intermediate state lacking long-range order as observed in Nd-227. Our results also show that insulating members of the iridate family have nearly identical magnetic ground states, and that the presence of magnetic A-site species does not play any significant role in altering the ground state properties.

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S. M. Disseler, Chetan Dhital, A. Amato, S. R. Giblin, Clarina de la Cruz, Stephen D. Wilson, M. J. Graf. 2012-03-29. Magnetic Order in the Pyrochlore Iridates A2Ir2O7 (A = Y, Yb). https://doi.org/10.1103/physrevb.86.014428

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