Size and interface effects on critical temperatures of ferromagnetic, ferroelectric and superconductive nanocrystals

Based on a size-dependent cohesive energy model, the size-dependent critical transition temperatures T-c(D) of ferromagnetic, ferroelectric and superconductive nanocrystals are modeled in a unified form without any adjustable parameter, where D denotes the diameter of nanoparticles and nanowires or the thickness of thin films. In terms of this model, T-c(D) depends on both size and interface conditions. The predicted results are in good agreement with the experimental and other theoretical results for free nanoparticles and nanowires and thin films with different substrate conditions. (c) 2005 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.