Comparison of dynamic behavior of ferroelectric and ferromagnetic nematic suspensions

TL;DR

This paper compares the dynamic fluctuation spectra of ferroelectric and ferromagnetic nanoparticle suspensions in nematic liquid crystals, revealing differences in particle-matrix coupling and their effects on orientational fluctuations.

Contribution

It provides the first comparative analysis of ferroelectric and ferromagnetic nanoparticle suspensions in nematic hosts using dynamic light scattering.

Findings

Different coupling mechanisms between particles and nematic matrix.

Distinct fluctuation spectra for ferroelectric and ferromagnetic suspensions.

Insights into how particle type influences liquid crystal dynamics.

Abstract

The pioneering realization of suspensions of ferroelectric nanoparticles in a nematic host was one of excellent contributions of Yuri Reznikov to the science of liquid crystals [Y. Reznikov et al., Appl. Phys. Lett. 82 (2003) 191]. This achievement created great excitement as entailed the enhancement of materials dielectric properties and increase of the phase transition temperature between nematic and isotropic phase. In this contribution, we examine the spectrum of fundamental fluctuations in one of his ferroelectric suspensions by dynamic light scattering measurements, which gives insight into the coupling between the particles and the orientation of the liquid crystalline matrix. We set side by side these results with the equivalent ones obtained for the case of stable suspensions of ferromagnetic nanoplatelets in a nematic matrix showing macroscopic ferromagnetic ordering. The underlying origin of the difference between the particle-matrix coupling observed in both cases is discussed and its effect on the orientational fluctuations spectrum is compared.