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arXiv · 1103.4319

Ferroelectricity from spin supercurrents in LiCuVO4

M. Mourigal·M. Enderle·R. K. Kremer·J. M. Law·B. Fåk
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Abstract

We have studied the magnetic structure of the ferroelectric frustrated spin-1/2 chain material LiCuVO4 in applied electric and magnetic fields using polarized neutrons. A symmetry and mean-field analysis of the data rules out the presence of static Dzyaloshinskii-Moriya interaction, while exchange striction is shown to be negligible by our specific-heat measurements. The experimentally observed magnetoelectric coupling is in excellent agreement with the predictions of a purely electronic mechanism based on spin supercurrents.

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M. Mourigal, M. Enderle, R. K. Kremer, J. M. Law, B. Fåk. 2011-03-22. Ferroelectricity from spin supercurrents in LiCuVO4. https://doi.org/10.1103/physrevb.83.100409

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