MAGNETIC-FIELD EFFECTS IN DIRECT-GAP AND INDIRECT-GAP SEMICONDUCTOR QUANTUM DOTS

A magnetic circular dichroism (MCD) measurement is utilized to investi gate confined states in direct (CuCl, and CdSxSe1-x) and indirect gap (Si) semiconductor quantum dots (QD's). CuCl and CdSxSe1-x, QD's belon g to the weak and intermediate confinement regimes, leading to contras tive response to a magnetic field. In CuCl QD's, the enhancement of g- value is observed due to the mixing of the relative and the center-of- mass motions, while (p, P)-type transition is observed in CdSxSe1-x QD 's. In Si QD's confined states with direct as well as indirect nature are observed that confirms the quantum confinement effects in Si QD's.