Fabrication of Cd_1-xMn_xTe Microcrystals by the Laser Ablation Method

Abstract

Microcrystals of the diluted magnetic semiconductor Cd_1-xMn_xTe(x=0.13,0.16) were fabricaed by the laser ablation method to investigate the formation process of the microcrystals and their magneto-optic effect. Microcrystals 20-40Å in diameter were observed by scanning tunneling microscopy and transmission electron microscopy. In the initial stage of the microcrystals' frowth, they had forms like circular plates. As the Cd_1-xMn_xTe evaporation increased, they became larger and rounder. X-ray diffraction showed the mixing of zinc-blende and wurtzite structures. The magnetic circular dichroism (MCD) spectra of the microcrystals were different from those of Cd_1-xMn_xTe thick films. The MCD peak, which reflects the band gap,shifted to a higher energy as the diameter of the microcrystal decreased. This energy shift was analyzed by using a quantum confinement model.