Fine Particle Size Effect of Metallic Al

Abstract

Metallic fine particles of Al with diameters of less than 100 Å are studied by NMR and magnetic susceptibility measurements at low temperatures to verify discrete energy level effect of conduction electrons. Different behaviors of particles with odd and even electron numbers are observed in NMR line shapes. Odd particles tend to have high paramagnetic susceptibility while even particles tend to zero paramagnetism. No appreciable enhancement of superconducting transition temperature is observed in fine particles. Some measurements of Cu particles are also carried out to be compared with Al particles.