Dielectric Spectroscopy of an Antiferroelectric Liquid Crystal for Two Cell Thicknesses

Abstract

The dielectric spectroscopy of an antiferroelectric liquid crystal (S)-4-(1-methylheptyloxycarbonyl)phenyl-4′-(6-pentanoyloxyhex-1-oxy)biphenyl-4-carboxylate for its homogeneous anchoring has been carried out for 10 μm and 4 μm cell thicknesses. This study suggests that the dielectric strength of Goldstone mode of the SmC* phase is significantly diminished from ∼195 to ∼69, whereas its relaxation frequency is increased from ∼2 kHz to ∼4 kHz from the higher to lower cell thickness. Alternatively, these parameters for the soft mode detected in the SmA* phase and for the two antiferroelectric relaxation modes detected in the phase do not show any appreciable change with the cell thickness.

Keywords:

• Antiferroelectric
• dielectric strength
• Goldstone mode
• relaxation frequency
• soft mode

Acknowledgment

We thank the Department of Science & Technology, Government of India for financial assistance under a research project (Grant no. SR/S2/CMP–45/2004). One of the authors (S.K.) also thanks CSIR (New Delhi) for providing SRF.