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arXiv · 1705.04246

Itinerant G-type antiferromagnetic order in SrCr$_2$As$_2$

Pinaki Das·N. S. Sangeetha·George R. Lindemann·T. W. Heitmann·A. Kreyssig·A. I. Goldman·R. J. McQueeney·D. C. Johnston·D. Vaknin
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Abstract

Neutron diffraction and magnetic susceptibility studies of a polycrystalline SrCr$_2$As$_2$ sample reveal that this compound is an itinerant G-type antiferromagnet below the N${\rm \acute{e}}$el temperature $T_{\textrm N}$ = 590(5) K with the Cr magnetic moments aligned along the tetragonal $c$ axis. The system remains tetragonal to the lowest measured temperature ($\sim$12 K). The lattice parameter ratio $c/a$ and the magnetic moment saturate at about the same temperature below $\sim$ 200 K, indicating a possible magnetoelastic coupling. The ordered moment, $\mu=1.9(1)~\mu_{\rm B}$/Cr, measured at $T = 12$ K, is significantly reduced compared to its localized value ($4~\mu_{\rm B}$/Cr) due to the itinerant character brought about by the hybridization between the Cr $3d$ and As $4p$ orbitals.

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Pinaki Das, N. S. Sangeetha, George R. Lindemann, T. W. Heitmann, A. Kreyssig, A. I. Goldman, R. J. McQueeney, D. C. Johnston, D. Vaknin. 2017-05-11. Itinerant G-type antiferromagnetic order in SrCr$_2$As$_2$. https://doi.org/10.1103/physrevb.96.014411

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