Eur. Phys. J. B 63, 205-209 (2008)
https://doi.org/10.1140/epjb/e2008-00240-8

Landau theory of ferroelectric transition in long cylindrical nanoparticles

Department of Physics, Banaras Hindu University, Varanasi, 221005, India

Corresponding author: ^a pkhare15@gmail.com

Received: 18 February 2008
Revised: 8 April 2008
Published online: 20 June 2008

Abstract

Using a phenomenological Landau theory, the size dependence on ferroelectric transition for free-standing long cylindrical nanoparticles is discussed. We derive the size dependence of the transition temperature, polarization profile as well as the static susceptibility. The transition temperature vanishes below a critical size where the static susceptibility shows divergence obeying Curie-Weiss law. In order to make this result compared with experiments, the average polarization and the susceptibility is computed with a Gaussian particle size distribution. The average polarization in such a case shows smearing with respect to the particle size whereas the divergence in the susceptibilty gets rounded. This might correspond to a size dependent soft mode which can be observed in Raman measurement.