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Nature of the Magnetic Order in the Charge-Ordered Cuprate La$_{1.48}$Nd$_{0.4}$Sr$_{0.12}$CuO$_4$

N. B. Christensen·H. M. Ronnow·J. Mesot·R. A. Ewings·N. Momono·M. Oda·M. Ido·M. Enderle·D. F. McMorrow·A. T. Boothroyd
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Abstract

Using polarized neutron scattering we establish that the magnetic order in La$_{1.48}$Nd$_{0.4}$Sr$_{0.12}$CuO$_4$ is either (i) one dimensionally modulated and collinear, consistent with the stripe model or (ii) two dimensionally modulated with a novel noncollinear structure. The measurements rule out a number of alternative models characterized by 2D electronic order or 1D helical spin order. The low-energy spin excitations are found to be primarily transversely polarized relative to the stripe ordered state, consistent with conventional spin waves.

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N. B. Christensen, H. M. Ronnow, J. Mesot, R. A. Ewings, N. Momono, M. Oda, M. Ido, M. Enderle, D. F. McMorrow, A. T. Boothroyd. 2007-05-09. Nature of the Magnetic Order in the Charge-Ordered Cuprate La$_{1.48}$Nd$_{0.4}$Sr$_{0.12}$CuO$_4$. https://doi.org/10.1103/physrevlett.98.197003

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