Study of capacitance of 5 different ferroelectric nematic liquid crystals with temperature

Ferroelectric nematic liquid crystals (FNLCs) are an emerging class of materials with spontaneous polarization, making them highly attractive for next-generation display technologies, sensors, and tunable optical devices. FNLCs are known to exhibit intriguing dielectric behavior under various conditions, but many fundamental aspects remain unresolved. Prior studies have reported exceptionally high dielectric constants in these materials, but recent work by Clark et al. (Phys. Rev. Res. 6, 013195, 2024) suggests that these measurements may primarily reflect the capacitance of insulating interfacial layers rather than the intrinsic dielectric properties of the FNLCs themselves. In our study, we partially confirm this interpretation. We measured the capacitance and loss of five distinctly different FNLC materials under identical conditions. Four materials exhibit the same capacitance values; values that do not change with temperature. In contrast, the loss for all materials varies widely. This further calls into the question the validity of using simple capacitance measurements to determine the dielectric properties of FNLC materials.