On the acoustic–director interaction in the smectic A phase

A model was previously proposed for the interaction energy between an acoustic field and the local nematic director. The consistency of this model was verified through nuclear magnetic relaxation and optical experiments. The model was later extended to the smectic A phase, despite the fact that the smectic essence of the problem was never included in the interaction process. In this work we investigate details of this interaction through the inclusion of elemental features of the smectic phase. We show that the acoustic–director interaction can be enhanced if the external acoustic field matches an eigenmode of the smectic system.