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arXiv · 1103.2862

The Magnetic Structure of $Er_{2}Ti_{2}O_{7}$

A. K. R. Briffa·R. J. Mason·M. W. Long
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Abstract

We employ the previously published neutron scattering experiments\cite{1,2,3} to suggest that Er$_2$Ti$_2$O$_7$ has a broken-symmetry multiple-{\bf q} state with tetragonal magnetic symmetry\cite{4}. The ordered moments do not appear to lie close to the crystal-field anticipated directions\cite{5} and we suggest that the low energy gapless mode, visible in specific-heat measurements\cite{6}, is not of the usual transverse isotropic Goldstone-mode type, but is longitudinal and is associated with the internal transfer of magnetism between distinct magnetic Bragg spots.

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A. K. R. Briffa, R. J. Mason, M. W. Long. 2011-03-15. The Magnetic Structure of $Er_{2}Ti_{2}O_{7}$. https://doi.org/10.1103/physrevb.84.094427

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