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arXiv · 1405.2704

Mapping the first order magnetic transition in Yb$_2$Ti$_2$O$_7$

E. Lhotel·S. R. Giblin·M. R. Lees·G. Balakrishnan·L. J. Chang·Y. Yasui
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Abstract

The very nature of the ground state of the pyrochlore compound Yb$_2$Ti$_2$O$_7$ is much debated, as experimental results demonstrate evidence for both a disordered or a long-range ordered ground state. Indeed, the delicate balance of exchange interactions and anisotropy is believed to lead to competing states, such as a Quantum Spin Liquid state or a ferromagnetic state which may originate from an Anderson-Higgs transition. We present a detailed magnetization study demonstrating a first order ferromagnetic transition at 245 mK and 150 mK in a powder and a single crystal sample respectively. Its first-order character is preserved up to applied fields of $\sim$ 200 Oe. The transition stabilizes a ferromagnetic component and involves slow dynamics in the magnetization. Residual fluctuations are also evidenced, the presence of which might explain some of the discrepancies between previously published data for Yb$_2$Ti$_2$O$_7$.

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E. Lhotel, S. R. Giblin, M. R. Lees, G. Balakrishnan, L. J. Chang, Y. Yasui. 2014-05-12. Mapping the first order magnetic transition in Yb$_2$Ti$_2$O$_7$. https://arxiv.org/abs/1405.2704

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