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arXiv · 1505.04995

Long range antiferromagnetic order of formally non-magnetic Eu$^{3+}$ Van Vleck ions observed in multiferroic Eu$_{1-x}$Y$_{x}$MnO$_3$

Arvid Skaugen·Enrico Schierle·Gerrit van der Laan·Dinesh K. Shukla·Helen C. Walker·Eugen Weschke·Jörg Strempfer
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Abstract

We report on resonant magnetic x-ray scattering and absorption spectroscopy studies of exchange-coupled antiferromagnetic ordering of Eu$^{3+}$ magnetic moments in multiferroic Eu$_{1-x}$Y$_{x}$MnO$_3$ in the absence of an external magnetic field. The observed resonant spectrum is characteristic of a magnetically ordered $^7F_1$ state that mirrors the Mn magnetic ordering, due to exchange coupling between the Eu $4f$ and Mn $3d$ spins. This is the first observation of long range magnetic order generated by exchange coupling of magnetic moments of formally non-magnetic Van Vleck ions, which is a step further towards the realization of exotic phases induced by exchange coupling in systems entirely composed of non-magnetic ions.

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Arvid Skaugen, Enrico Schierle, Gerrit van der Laan, Dinesh K. Shukla, Helen C. Walker, Eugen Weschke, Jörg Strempfer. 2015-05-19. Long range antiferromagnetic order of formally non-magnetic Eu$^{3+}$ Van Vleck ions observed in multiferroic Eu$_{1-x}$Y$_{x}$MnO$_3$. https://doi.org/10.1103/physrevb.91.180409

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