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arXiv · 1209.1780

Neutron Brillouin scattering with pulsed spallation neutron source - spin-wave excitations from ferromagnetic powder samples -

S. Itoh·Y. Endoh·T. Yokoo·D. Kawana·Y. Kaneko·Y. Tokura·M. Fujita
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Abstract

Neutron Brillouin scattering (NBS) method was developed using a pulsed spallation neutron source, and the feasibility of NBS was demonstrated by observing ferromagnetic spin waves in La$_{0.8}$Sr$_{0.2}$MnO$_3$ and SrRuO$_3$ powders. Gapless spin-wave excitations were observed in La$_{0.8}$Sr$_{0.2}$MnO$_3$, which were continuously extended to the lower scattering vector $Q$ from previous results using single crystals. The novel result is a well-defined quadratic $Q$ dependence in the spin-wave dispersion curve with a large energy gap in SrRuO$_3$ indicating robust spin-orbit coupling.

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S. Itoh, Y. Endoh, T. Yokoo, D. Kawana, Y. Kaneko, Y. Tokura, M. Fujita. 2012-09-09. Neutron Brillouin scattering with pulsed spallation neutron source - spin-wave excitations from ferromagnetic powder samples -. https://doi.org/10.7566/jpsj.82.043001

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