%0 journal article %@ 1098-0121 %A Grigoriev, S.V.,Sukhanov, A.S.,Altynbaev, E.V.,Siegfried, S.-A.,Heinemann, A.,Kizhe, P.,Maleyev, S.V. %D 2015 %J Physical Review B %N %P 220415 %R doi:10.1103/PhysRevB.92.220415 %T Spin waves in full-polarized state of Dzyaloshinskii-Moriya helimagnets: Small-angle neutron scattering study %U https://doi.org/10.1103/PhysRevB.92.220415 %X We develop the technique to study the spin-wave dynamics of the full-polarized state of the Dzyaloshinskii-Moriya helimagnets by polarized small-angle neutron scattering. We have experimentally proven that the spin-waves dispersion in this state has the anisotropic form. We show that the neutron scattering image displays a circle with a certain radius which is centered at the momentum transfer corresponding to the helix wave vector in helimagnetic phase k s , which is oriented along the applied magnetic field H . The radius of this circle is directly related to the spin-wave stiffness of this system. This scattering depends on the neutron polarization showing the one-handed nature of the spin waves in Dzyaloshinskii-Moriya helimagnets in the full-polarized phase. We show that the spin-wave stiffness A for MnSi helimagnet decreased twice as the temperature increases from zero to the critical temperature Tc.