SPIN-DENSITY WAVES IN CR UNDER A MAGNETIC-FIELD

The twisting of the spin-density wave (SDW) in Cr in the transverse SD W phase has been examined by neutron scattering experiments in a magne tic field. Twisting beyond experimental errors was observed, but the t wisting angle is very small compared to the rotation angle of the SDW in the magnetic held. This result is consistent with the fact that the transverse spin fluctuation in the Cr SDW is strongly suppressed at l ow excitation energies. The anisotropy energy of the SDW in Cr is also discussed.