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Birefringence and order parameter studies in ferroelectric liquid crystals using laser transmission technique

  • B. Gowri Sankara Rao , K. Mallika , Sie Tiong Ha and S. Sreehari Sastry EMAIL logo
Published/Copyright: December 14, 2020

Abstract

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.


Corresponding author: S. Sreehari Sastry, Department of Physics, Acharya Nagarjuna University, Nagarjunanagar, 522 510, India, E-mail:

Funding source: University Grants Commission

Award Identifier / Grant number: No. F.18-1/2011

Funding source: University Grants Commission Departmental Special Assistance

Award Identifier / Grant number: No.: F.530/1/DSA-1/2015 (SAP-1)

Acknowledgments

One of the authors (SSS) is grateful to University Grants Commission for providing BSR Faculty fellowship No. F.18-1/2011 (BSR) Dt: 04/01/2017. The authors also gratefully acknowledge University Grants Commission Departmental Special Assistance at Level I program No.: F.530/1/DSA-1/2015 (SAP-1), dated 12 May 2015.

  1. Author contribution: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.

  2. Research funding: This work was supported by University Grants Commission for providing BSR Faculty fellowship No. F.18-1/2011(BSR) Dt: 04/01/2017. The authors also gratefully acknowledge University Grants Commission Departmental Special Assistance at Level I program No.: F.530/1/ DSA-1/2015 (SAP-1), dated 12 May 2015.

  3. Conflict of interest statement: The authors declare no conflicts of interest regarding this article.

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Received: 2020-08-21
Accepted: 2020-10-30
Published Online: 2020-12-14
Published in Print: 2021-02-23

© 2020 Walter de Gruyter GmbH, Berlin/Boston

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