Electric field tuning of spin splitting in a quantum dot coupled to a semimagnetic quantum dot

Abstract

We develop an approach for tuning the spin splitting and g-factor of a quantum dot by coupling it to semi-magnetic quantum dot and tuning the electric field. We show that spin splittings and g-factors of the states of a non-magnetic quantum dot coupled to semimagnetic quantum dot can be enhanced orders of magnitude. Evaluations are made for coupled CdTe/CdMnTe quantum dots. These effects are caused by electric field control of repulsion of spin sublevels in the non-magnetic dot due to tunnel coupling of quantum dots. Electric field control of spin splittings in quantum dots is of potential interest in connection with spin qubit rotations for quantum computation.