Size‐Dependent Chemical and Magnetic Ordering in <i>L</i>1₀‐FePt Nanoparticles

Direct evidence for size-dependent chemical and magnetic ordering in L10-FePt nanoparticles is obtained by measuring monodisperse nanoparticles prepared by the "salt-matrix annealing" technique. Quantitative correlations show that the long-range chemical-ordering parameter, Curie temperature (see figure), and saturated magnetization drop significantly with decreasing particle size.