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Spin dynamics in stripe-ordered La5/3Sr1/3NiO4

A. T. Boothroyd·D. Prabhakaran·P. G. Freeman·S. J. S. Lister·M. Enderle·A. Hiess·J. Kulda
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Abstract

Polarized and unpolarized neutron inelastic scattering has been used to measure the spin excitations in the spin-charge-ordered stripe phase of La5/3Sr1/3NiO4. At high energies, sharp magnetic modes are observed characteristic of a static stripe lattice. The energy spectrum is described well by a linear spin wave model with intra- and inter-stripe exchange interactions between neighbouring Ni spins given by J = 15 +/- 1.5 meV and J' = 7.5 +/- 1.5 meV respectively. A pronounced broadening of the magnetic fluctuations in a band between 10 meV and 25 meV is suggestive of coupling to collective motions of the stripe domain walls.

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A. T. Boothroyd, D. Prabhakaran, P. G. Freeman, S. J. S. Lister, M. Enderle, A. Hiess, J. Kulda. 2002-06-27. Spin dynamics in stripe-ordered La5/3Sr1/3NiO4. https://doi.org/10.1103/physrevb.67.100407

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