Nonlinear Electro-Optics of Colloidal Crystals as Studied by Reflection Spectroscopy

✍ Scribed by Tsuneo Okubo; Akira Tsuchida; Shinji Okada; Shinnen Kobata

• Publisher: Elsevier Science
• Year: 1998
• Tongue: English
• Weight: 183 KB
• Volume: 199
• Category: Article
• ISSN: 0021-9797
• DOI: 10.1006/jcis.1997.5330

✦ Synopsis

of visible light (1-4). Since the Bragg condition can be Nonlinear electro-optic behavior of colloidal crystals of colloidal modulated by an external electric field, it is possible to silica spheres is studied by the reflection intensity measurements change the reflection color from the crystals by the electric and the time-resolved reflection spectroscopy. Harmonic generafield. This phenomenon called the electro-optic effect intion is observed for the reflection signal when a sine-wave electric duces changes in the optical properties such as electric birefield ranging from 0.01 to 10 Hz is applied. The synchronous fringence, light-scattering intensity, dichroism, reflection, fluctuation of the colloidal spheres containing expanded electrical and transmitted-light spectroscopy. double layers in the crystal lattices is one of the main causes for Stoimenova et al. have studied the electro-optic effects of the electro-optics. It is deduced from the time-resolved reflection colloidal suspensions by the method of electric light scatterspectra analyses that the transformation between two subphases of lattice structures, fcc and bcc, is also an important factor for ing (11-13). In this method, the electro-optic effect a Å the harmonic generation. ᭧ 1998 Academic Press (I e 0 I o )/I o was measured, where I e and I o are the scattered Key Words: electro-optics; colloidal crystal; modulation; harlight intensity in the presence and in the absence of an elecmonics; synchronization.

tric field, respectively. This method is advantageous for analyzing the dynamic modes in colloidal systems and their variation in the course of colloidal phase transition. Recently,