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arXiv · 2205.00810

Novel quantum phase of the chromium spinel oxide HgCr$_{\rm 2}$O$_{\rm 4}$ in high magnetic fields

Shojiro Kimura·Shusaku Imajo·Masaki Gen·Tsutomu Momoi·Masayuki Hagiwara·Hiroaki Ueda·Yoshimitsu Kohama
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Abstract

In this study, we have performed the magnetocaloric effect and the specific heat measurements of chromium spinel oxide HgCr$_2$O$_4$, wherein the magnetic Cr$^{3+}$ ions form a highly frustrated pyrochlore lattice with significant spin-lattice coupling. In addition to the known magnetic-field-induced phases, our thermodynamic measurements detect a novel quantum phase just before the saturation of the magnetization, which has not been expected from the classical theories of the pyrochlore lattice antiferromagnet with spin-lattice coupling. Based on recent theoretical model calculation, we discuss the possibility of a spin nematic state appearing for this quantum phase.

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Shojiro Kimura, Shusaku Imajo, Masaki Gen, Tsutomu Momoi, Masayuki Hagiwara, Hiroaki Ueda, Yoshimitsu Kohama. 2022-05-02. Novel quantum phase of the chromium spinel oxide HgCr$_{\rm 2}$O$_{\rm 4}$ in high magnetic fields. https://doi.org/10.1103/physrevb.105.l180405

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