An experimental study of critical phenomena in thin ferroelectric films is presented which, for the first time, conclusively demonstrates that the polarization in thin films is drastically reduced as a result of depolarization effects. Other causes, like impurities, structural defects, and domain formation, which can lead to reduction of polarization, are ruled out.

• Received 18 May 1973

DOI:https://doi.org/10.1103/PhysRevLett.30.1218