Ultrasonic attenuation in the transverse spin density wave phase of chromium

A strong hysteretic attenuation peak is seen when a polarizing field itH p is applied perpendicular to both the longitudinal ultrasonic wavevector itq and the wavevector itQ of the transverse spin density wave (TSDW) in chromium, i.e., itH p⊥ itq⊥ itQ, but not when ( itH p∥ itq)⊥ itQ. This effect is discussed in relation to the various models for the configuration of the polarization that have been proposed to explain the anomalous attenuation seen in the TSDW phase for itq⊥ itQ.