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 It should be noted that at some temperatures below the dielectric constant maximum, the relaxor polymer exhibits large polarization hysteresis, which is another characteristic of ferroelectric relaxors