Dyuthi @ CUSAT >
e-SCHOLARSHIP >
Photonics >
Faculty >
Dr.C P Girijavallabhan >
Please use this identifier to cite or link to this item:
http://purl.org/purl/2496
|
Title: | Laser Induced Photoacoustic Technique for the Detection of Phase Transitions in Liquid Crystals |
Authors: | Nibu, A George Vallabhan, C P G Nampoori, V P N George, A K Radhakrishnan, P Technology |
Keywords: | Photoacoustic technique Heptyl-oxy-cyanobiphenyl Rosencwaig-Gersho Nematic transition |
Issue Date: | 2001 |
Publisher: | Taylor & Francis |
Abstract: | In this paper we report the use of a laser induced phoroacoustic technique for the detection of multiple phase transitions in heptyl-oxy-cyanobiphenyl (70CB) and octyl-oxy-cyanobiphenyl (80CB) liquid crystals. The observed photoacoustic signal amplitude profile carries clear signatures of two tirst order transitions in 70CB and two tirst order and a second order transitions in 80CB. Analysis of the experimental data using Rosencwaig-Gersho theory shows that the sudden decrease in the photoacoustic (PA) signal amplitude during phase transitions is due to a sharp increase in the heat capacity of the samples near the transition temperatures. |
URI: | http://dyuthi.cusat.ac.in/purl/2496 |
Appears in Collections: | Dr.C P Girijavallabhan
|
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.
|