SIZE DEPENDENCE OF THE CURIE-TEMPERATURE OF SEPARATE NICKEL PARTICLESSTUDIED BY INTERFERENCE ELECTRON-MICROSCOPY

Interference electron microscopy was applied to measure the size depen dence of the Curie temperature of small nickel particles. Nickel films consisting of particles of different sizes and distances between them were studied. We found a decrease of the Curie temperature with decre asing particle size for particles smaller than about 100 nm. The decay of the Curie temperature is stronger for particles being well separat ed from other particles, whereas the decay is much less pronounced in the case of small distances between the particles. This observation ca n be explained by interparticle interaction.