Abstract:
The ferroelectric phase transition on the free surface of a polymer ferroelectric Langmuir-Blodgett film was studied by the optical second harmonic generation (SHG) technique. A hysteresis in the temperature dependence of the SHG intensity observed for a multilayer film of a poly(vinylidene fluoride)-trifluoroethylene copolymer in the vicinity of $T\approx 15^\circ$ C is a manifestation of the first-order ferroelectric phase transition in the topmost surface monolayer of the film.