Birefringence and order parameter studies in ferroelectric liquid crystals using laser transmission technique
Autor: | Sie-Tiong Ha, S. Sreehari Sastry, K. Mallika, B. Gowri Sankara Rao |
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Rok vydání: | 2020 |
Předmět: |
010302 applied physics
Birefringence Phase transition temperature Materials science business.industry General Physics and Astronomy Order (ring theory) 02 engineering and technology 021001 nanoscience & nanotechnology Laser 01 natural sciences Ferroelectricity law.invention Transmission (telecommunications) law Liquid crystal 0103 physical sciences Optoelectronics Physical and Theoretical Chemistry 0210 nano-technology business Mathematical Physics |
Zdroj: | Zeitschrift für Naturforschung A. 76:163-168 |
ISSN: | 1865-7109 0932-0784 |
Popis: | Birefringence of the ferro electric liquid crystals (FLCs): (S)-(−)-2-methylbutyl 4′-(4ʺ-n-alkanoyloxybenzoyloxy) biphenyl-4-carboxylates (S-MB-nB-BC) where n = 16 and 18 is determined experimentally using laser transmission technique. In this experimental technique, the light coming out from the laser source (of wavelength 633 nm) passes through the polarizer and analyzer via FLC sample under crossed position. Optical intensities transmitted from the sample fall on the phototransistor through the analyzer. Phototransistor is a photo detector in which the transmitted light from the analyzer is converted into the electric response and measured in terms of voltage. These voltage measurements are used to determine the birefringence values of the samples. Further, order parameter is also determined. The results are compared with image analysis technique values along with phase transition temperatures, which are in good agreement. |
Databáze: | OpenAIRE |
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