The effect of ac field amplitude on the relaxor behaviors in Langmuir-Blodgett terpolymer films

The ac field (E-ac) amplitude dependence of dielectric response has been investigated for poly (vinylidene fluoride-trifluoroethylene-chlorofluoroethylene) relaxor terpolymer films. The frequency dependence of the temperature of the permittivity maximum T-m can be well described by the Vogel-Fulcher relation for E-ac in the range from 1.33 to 80 MV/m. T-m remains nearly constant at an E-ac level lower than 13.3 MV/m, and starts decreasing with E-ac increases further. The two parameters fitting to the Vogel-Fulcher relation, freezing temperature T-f and activation energy E-a, vary little for E-ac below 26.7 MV/m and then T-f decreases, while E-a increases for higher E-ac level.