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arXiv · 1907.12476

Hole Doping and Antiferromagnetic Correlations above the N{\'e}el temperature of the Topological Semimetal (Sr$_{1-x}$K$_x$)MnSb$_2$

Yong Liu·Farhan Islam·Kevin W. Dennis·Wei Tian·Benjamin G. Ueland·Robert J. McQueeney·David Vaknin
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Abstract

Neutron diffraction and magnetic susceptibility studies of orthorhombic single crystal {\Ksub} confirm the three dimensional (3D) C-type antiferromagnetic (AFM) ordering of the Mn$^{2+}$ moments at $T_{\rm N}=305 \pm 3$ K which is slightly higher than that of the parent SrMnSb$_2$ with $T_{\rm N}=297 \pm 3$ K. Susceptibility measurements of the K-doped and parent crystals above $T_{\rm N}$ are characteristic of 2D AFM systems. This is consistent with high temperature neutron diffraction of the parent compound that display persisting 2D AFM correlations well above $T_{\rm N}$ to at least $\sim 560$ K with no evidence of a ferromagnetic phase. Analysis of the de Haas van Alphen magnetic oscillations of the K-doped crystal is consistent with hole doping.

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Yong Liu, Farhan Islam, Kevin W. Dennis, Wei Tian, Benjamin G. Ueland, Robert J. McQueeney, David Vaknin. 2019-07-29. Hole Doping and Antiferromagnetic Correlations above the N{\'e}el temperature of the Topological Semimetal (Sr$_{1-x}$K$_x$)MnSb$_2$. https://doi.org/10.1103/physrevb.100.014437

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