Anomalous Sound Attenuation near Magnetic Critical Points

Abstract

Recently Tani and Morill reported the temperature dependence of the longitudinal sound attenuation in ferroand antiferromagnets near the critical points taking into account the distortion of the exchange interaction in a microscopic manner (using the continued fraction method2l). We consider the same model but in a semi-phenomenological way, from which we derive a different result. Following Tani and Mori's idea1l we write down the expression for the attenuation constant