For the dielectric constant, the P(VDF-TrFE) copolymer exhibits a sharp ferroelectric-paraelectric (F-P) transition at 110◦C (see Fig. 2) and the peak position does not depend on frequency. In contrast, the P(VDF-TrFE-CFE) terpolymer shows a much broad peak in the dielectric constant near room temperature and the peak position shifts progressively to higher temperature with frequency,which is a feature typical of ferroelectric relaxors [23]. It should be noted that at some tempera-tures below the dielectric constant maximum, the relaxor polymer exhibits large polarization hysteresis, which is another characteristic of fer