Figure 5. Multiferroic and dynamical properties of multi-q states.

Magnetic field dependence at K=0.04 of (a) the average spin vector 〈S〉, (b) the electric polarization vector P and (c) the imaginary part of the in-plane magnetic susceptibility, χ′′(ω) (arbitrary units). Black and red lines in a and b are the out-of-plane and in-plane components of the vectors. The electric polarization was calculated using equation (12) for g₁=g₂ and g₃=0. The inset in c shows magnetic modes in the 2q-state near the transition to the flop state.