Reversible propagating fingers in an antiferroelectric liquid crystal

Propagating fingerlike solitary waves are observed in an antiferroelectric liquid crystal on application of an electric field above a threshold field Eₜₕ. On reducing the field below Eₜₕ the fingers recede, also as solitary waves. The velocity of the waves, which to our knowledge is the fastest observed for a liquid crystal, scales approximately as E-Eₜₕ for E near Eₜₕ. A simple model, which includes a layer-layer coupling term, is presented and describes much of the observed behavior.