Direct Observation of Sinusoidal Ultrasonically Induced Birefringence in Liquid Crystal in the Isotropic Phase

Abstract

Direct observation of sinusoidal ultrasonically induced birefringence was successfully carried out in 4-cyano-4 0pentylbiphenyl in the isotropic phase. The temperature dependence of the birefringence per unit intensity was compared with the estimated value using the theoretical expression for ultrasonically induced birefringence based on the de Gennes' phenomenological theory for translational-reorientational coupling. The agreement of the experimental results with those from the estimation validates the theoretical treatment.

Polarization of Diffracted Light by Ultrasound in Liquids without Strong Orientational Cooperativity

“…Recently, we have observed the sinusoidal birefringence directly using a light beam narrower than the wavelength of ultrasound. 1) However, the method is limited to the lower frequency range because the wavelength of the ultrasound is inversely proportional to the frequency.…”