g-factor tuning in self-assembled quantum dots

摘要

The possibility of electrical tuning of exciton g-factors in self-assembled InAs/GaAs quantum dots is explored theoretically by means of a tight-binding-like effective bond-orbital approach. The electron g-factor in the dots of various sizes is found to exhibit very little change over a broad range of the field strength. In contrast, the ground hole state in the dots of high aspect ratio is seen very sensitive to the applied field, its g-factor even changes the sign with the field. The distinct behavior of the electron and hole g-factors in the presence of electric field is explained in terms of nonzero envelope orbital angular momentum carried by the hole states.