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arXiv · 2202.02220

Uniaxial pressure effects in the two-dimensional van-der-Waals ferromagnet CrI$_3$

J. Arneth·M. Jonak·S. Spachmann·M. Abdel-Hafiez·Y. O. Kvashnin·R. Klingeler
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Abstract

Magnetoelastic coupling and uniaxial pressure dependencies of the ferromagnetic ordering temperature in the quasi-two-dimensional layered van-der-Waals material CrI$_3$ are experimentally studied and quantified by high-resolution dilatometry. Clear anomalies in the thermal expansion coefficients at $T_{\rm C}$ imply positive (negative) pressure dependencies $\partial T_{\rm C}/\partial p_{\rm i}$ for pressure applied along (perpendicular to) the $c$ axis. The experimental results are backed up by numerical studies showing that the dominant, intra-layer magnetic coupling increases upon compression along the $c$ direction and decreases with negative in-plane strain. In contrast, inter-layer exchange is shown to initially increase and subsequently decrease upon the application of both out-of-plane and in-plane compression.

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J. Arneth, M. Jonak, S. Spachmann, M. Abdel-Hafiez, Y. O. Kvashnin, R. Klingeler. 2022-02-04. Uniaxial pressure effects in the two-dimensional van-der-Waals ferromagnet CrI$_3$. https://doi.org/10.1103/physrevb.105.l060404

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