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Magnetic excitations in La$_{1.5}$Sr$_{0.5}$CoO$_4$

L. M. Helme·A. T. Boothroyd·D. Prabhakaran·F. R. Wondre·C. D. Frost·J. Kulda
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Abstract

We report magnetization and neutron scattering measurements of the half-doped compound La$_{1.5}$Sr$_{0.5}$CoO$_4$, which exhibits a checkerboard pattern of charge ordering below ~800K. In the antiferromagnetically-ordered phase below \~40K the spins are found to be canted in the ab plane. The spin excitation spectrum includes spin-wave excitations with a maximum energy of 16 meV, and diffuse magnetic modes at energies around 30 meV.

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L. M. Helme, A. T. Boothroyd, D. Prabhakaran, F. R. Wondre, C. D. Frost, J. Kulda. 2003-10-31. Magnetic excitations in La$_{1.5}$Sr$_{0.5}$CoO$_4$. https://doi.org/10.1016/j.physb.2004.03.068

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