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arXiv · 0711.1745

An x-ray resonant diffraction study of multiferroic DyMn2O5

R. A. Ewings·A. T. Boothroyd·D. F. McMorrow·D. Mannix·H. C. Walker·B. M. R. Wanklyn
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Abstract

X-ray resonant scattering has been used to measure the magnetic order of the Dy ions below 40K in multiferroic DyMn$_{2}$O$_{5}$. The magnetic order has a complex behaviour. There are several different ordering wavevectors, both incommensurate and commensurate, as the temperature is varied. In addition a non-magnetic signal at twice the wavevector of one of the commensurate signals is observed, the maximum intensity of which occurs at the same temperature as a local maximum in the ferroelectric polarisation. Some of the results, which bear resemblence to the behaviour of other members of the RMn$_{2}$O$_{5}$ family of multiferroic materials, may be explained by a theory based on so-called acentric spin-density waves.

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R. A. Ewings, A. T. Boothroyd, D. F. McMorrow, D. Mannix, H. C. Walker, B. M. R. Wanklyn. 2007-11-12. An x-ray resonant diffraction study of multiferroic DyMn2O5. https://doi.org/10.1103/physrevb.77.104415

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