Low-pass RC filter modified by liquid crystal exhibiting one Debye relaxation - theoretical approach

Abstract

The solid dielectrics used in the capacitors exhibit rather high-frequency relaxations. This means that in the radio-frequency range, the capacitors exhibit a constant capacity. When a liquid crystal is put into the capacitors, it is observed that in the radio-frequency range the capacity changes (decreases with frequency). This is due to the fact that liquid crystals exhibit relaxation in the radio-frequency range. In this paper, the formulas for the electric response of a low-frequency RC filter with liquid crystal characterized by complex electric permittivity are derived. One Debye-type relaxation is assumed in the calculations. The influence of strengths and relaxation time (frequency) of relaxation mode in liquid crystal on the electric response of low-frequency filters is discussed.