OBSERVATION OF EXOTIC SUBPHASES IN AN ANTIFERROELECTRIC LIQUID-CRYSTAL

Dielectric and polarization measurements are carried out for character izing the subphases in a antiferroelectric liquid crystal with a varie ty of ferri-, ferro- and antiferroelectric phases. It is found that fe rri- phases in between SmCA are somewhat unstable and disordered; the reasons of the instability are given in terms of the ANNI model. A met a-stable field induced ferri phase has been found thus confirming our discovery (Panarin et al Phys. Rev. E 55, 4345, 1997) of such a ferri phase. A surface domain mode having a frequency about a decade higher than that of the Goldstone mode has also been observed for the first t ime in a antiferroelectric liquid crystal.