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arXiv · 1911.12103

Spin-lattice coupling in a ferrimagnetic spinel: The exotic $H$-$T$ phase diagram of MnCr$_2$S$_4$ up to 110 T

A. Miyata·H. Suwa·T. Nomura·L. Prodan·V. Felea·Y. Skourski·J. Deisenhofer·H. -A. Krug von Nidda·O. Portugall·S. Zherlitsyn·V. Tsurkan·J. Wosnitza·A. Loidl
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Abstract

In antiferromagnets, the interplay of spin frustration and spin-lattice coupling has been extensively studied as the source of complex spin patterns and exotic magnetism. Here, we demonstrate that, although neglected in the past, the spin-lattice coupling is essential to ferrimagnetic spinels as well. We performed ultrahigh-field magnetization measurements up to 110 T on a Yafet-Kittel ferrimagnetic spinel, MnCr$_2$S$_4$, which was complemented by measurements of magnetostriction and sound velocities up to 60 T. Classical Monte Carlo calculations were performed to identify the complex high-field spin structures. Our minimal model incorporating spin-lattice coupling accounts for the experimental results and corroborates the complete phase diagram, including two new high-field phase transitions at 75 and 85 T. Magnetoelastic coupling induces striking effects: An extremely robust magnetization plateau is embedded between two unconventional spin-asymmetric phases. Ferrimagnetic spinels provide a new platform to study asymmetric and multiferroic phases stabilized by spin-lattice coupling.

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A. Miyata, H. Suwa, T. Nomura, L. Prodan, V. Felea, Y. Skourski, J. Deisenhofer, H. -A. Krug von Nidda, O. Portugall, S. Zherlitsyn, V. Tsurkan, J. Wosnitza, A. Loidl. 2019-11-27. Spin-lattice coupling in a ferrimagnetic spinel: The exotic $H$-$T$ phase diagram of MnCr$_2$S$_4$ up to 110 T. https://doi.org/10.1103/physrevb.101.054432

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