Abstract :
We observed a giant splitting of exciton spin sublevels in CdS nanocrystals, each doped on the average by one Mn ion. The splitting, which exists in zero external magnetic field, is caused by the gigantic internal magnetic field of the Mn ion and results from the enhancement of the short range spin–spin interactions in nanocrystal quantum dots. The splitting is seen in the strong magnetic circular dichroism of the CdS band edge transitions. The magnitude of the observed band edge splitting is in good agreement with a theoretical calculation of the effective magnetic field.
