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arXiv · 1101.0619

Low energy, quasi-one-dimensional, spin dynamics in charge-ordered La(2-x)Sr(x)NiO(4)

P. G. Freeman·D. Prabhakaran·K. Nakajima·A. Stunault·M. Enderle·C. Niedermayer·K. Yamada·A. T. Boothroyd
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Abstract

The low energy spin excitations of La(2-x)Sr(x)NiO(4), x = 0.275 and 1/3, have been investigated by unpolarized- and polarized-inelastic neutron scattering from single crystals. A pattern of magnetic diffuse scattering is observed in both compositions, and is consistent with quasi-one-dimensional AFM spin correlations along the charge stripes. Analysis of the energy lineshape for x = 1/3 indicates that the diffuse scattering is inelastic with a characteristic energy of 1.40 +/- 0.07 meV. There is no discernible difference between the diffuse scattering from x = 0.275 and x = 1/3, suggesting that it is an intrinsic property of the charge stripes.

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P. G. Freeman, D. Prabhakaran, K. Nakajima, A. Stunault, M. Enderle, C. Niedermayer, K. Yamada, A. T. Boothroyd. 2011-01-03. Low energy, quasi-one-dimensional, spin dynamics in charge-ordered La(2-x)Sr(x)NiO(4). https://doi.org/10.1103/physrevb.83.094414

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