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Spin fluctuations in the stacked-triangular antiferromagnet YMnO3

B. Roessli·S. N. Gvasaliya·E. Pomjakushina·K. Conder
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Abstract

The spectrum of spin fluctuations in the stacked-triangular antiferromagnet YMnO3 was studied above the Neel temperature using both unpolarized and polarized inelastic neutron scattering. We find an in-plane and an out-of-plane excitation. The in-plane mode has two components just above TN, a resolution-limited central peak and a Debye-like contribution. The quasi-elastic fluctuations have a line-width that increases with q like Dq^z and the dynamical exponent z=2.3. The out-of-plane fluctuations have a gap at the magnetic zone center and do not show any appreciable q-dependence at small wave-vectors.

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B. Roessli, S. N. Gvasaliya, E. Pomjakushina, K. Conder. 2005-03-09. Spin fluctuations in the stacked-triangular antiferromagnet YMnO3. https://doi.org/10.1134/1.1931017

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