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arXiv · 1311.5526

Static magnetic moments revealed by muon spin relaxation and thermodynamic measurements in quantum spin ice Yb$_2$Ti$_2$O$_7$

Lieh-Jeng Chang·Martin R. Lees·Isao Watanabe·Adrian D. Hillier·Yukio Yasui·Shigeki Onoda
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Abstract

We present muon spin relaxation ($μ$SR) and specific-heat versus temperature $C(T)$ measurements on polycrystalline and single-crystal samples of the pyrochlore magnet Yb$_2$Ti$_2$O$_7$. $C(T)$ exhibits a sharp peak at a $T_\mathrm{C}$ of 0.21 and 0.26~K for the single-crystal and polycrystalline samples respectively. For both samples, the magnetic entropy released between 50~mK and 30~K amounts to $R\ln2$ per Yb. At temperatures below $T_\mathrm{C}$ we observe a steep drop in the asymmetry of the zero-field $μ$SR time spectra at short time scales, as well as a decoupling of the muon spins from the internal field in longitudinal magnetic fields of $\leq0.25$~T for both the polycrystalline and single-crystal samples. These muon data are indicative of static magnetic moments. Our results are consistent with the onset of long-range magnetic order in both forms of Yb$_2$Ti$_2$O$_7$.

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Lieh-Jeng Chang, Martin R. Lees, Isao Watanabe, Adrian D. Hillier, Yukio Yasui, Shigeki Onoda. 2014-05-07. Static magnetic moments revealed by muon spin relaxation and thermodynamic measurements in quantum spin ice Yb$_2$Ti$_2$O$_7$. https://doi.org/10.1103/physrevb.89.184416

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