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Chiral fluctuations in MnSi above Tc

B. Roessli·P. Boeni·W. E. Fischer·Y. Endoh
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Abstract

Polarized neutrons are used to determine the antisymmetric part of the magnetic susceptibility in non-centrosymmetric MnSi. The paramagnetic fluctuations are found to be incommensurate with the chemical lattice and to have a chiral character. We argue that antisymmetric interactions must be taken into account to properly describe the critical dynamics in MnSi above T$_C$. The possibility of directly measuring the polarization dependent part of the dynamical susceptibility in a large class of compounds through polarised inelastic neutron-scattering is outlined as it can yield direct evidence for antisymmetric interactions like spin-orbit coupling in metals as well as in insulators.

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B. Roessli, P. Boeni, W. E. Fischer, Y. Endoh. 2002-01-18. Chiral fluctuations in MnSi above Tc. https://arxiv.org/abs/cond-mat/0201327

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