Conduction-Electron Spin Resonance in Fine Particles of Magnesium and Calcium

Abstract

The conduction-electron spin resonance (CESR) of Mg arid Ca fine particles produced by the gas evaporation technique was observed at 9.1 GHz in the temperature range from 2.7 K to room temperature and at 35 GHz at room temperature. In Mg fine particles, a broad and an anomalous narrow resonance lines were observed one over the other. The former showed the same Pauli paramagnetic behavior as the bulk metal in the temperature dependence, and the latter the increase of the absorption intensity with decreasing temperature like the Curie law. In Ca fine particles, only the anomalous narrow line was observed. Those narrow lines were thought to be due to the smallness of size and be composed of numerous spin packets with different g values and linewidths, and are discussed in relation to the quantum size effect.