Solid-like dynamics in ultrathin films of polymeric liquids

The fast dynamics in ultrathin films of polymeric liquids was analyzed. The dynamic behavior was obtained by deforming the film under oscillating electric field and measuring the electrostrictive strain by the interferometric method. The dynamic response of thin films as a function of frequency in the 10-64 kHz or 100-16 μs range indicated that the electrostrictive dynamics was primarily elastic. The amplitude modulation due to the change in reflectivity from the sample due to electric field was found to be well within the noise.