Electric Response of a Negative Dielectric Anisotropy Nematic Liquid Crystal Doped with Ionic Dopant

Abstract:

The electrical properties measurements have been performed in a homogeneous alignment parallelepiped cell containing 4-methoxy benzylidene- 4-butylaniline (MBBA) liquid crystal doped with 0.02%wt tetrabutylammonium bromide (TBAB). The measurement of the complex permittivity was conducted in the nematic phase, covering a frequency range of 42 Hz to 5 MHz. A new relaxation mode was observed in the low-frequency region, which was not present in pure MBBA. The obtained dielectric dispersion could be fitted using the double Cole–Cole formula to determine the relaxation frequencies. The steady-state current exhibited a nonlinear dependence on the applied voltage, and hysteresis was observed in the transient current-voltage characteristic curve.

• Periodical: Key Engineering Materials (Volume 991)
• Pages: 21-27
• DOI: https://doi.org/10.4028/p-1rvxKO
• Online since: October 2024
• Authors: Andika Fajar*, Heri Jodi, Riyani Tri Yulianti, Rike Yudianti, Suryadi Suryadi, Ervanggis Minggar Kusumasari, Yusril Yusuf
• Keywords: Dielectric, Ionic Dopant, Nematic Liquid Crystal, Steady-State Current, Transient Current

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