Rashba spin splitting of the minibands of coupled InAs∕GaAs pyramid quantum dots

The Rashba spin splitting of the minibands of coupled InAs∕GaAs pyramid quantum dots is investigated using the k⋅p method and valence force field model. The Rashba splitting of the two dimensional miniband in the lateral directions is found due to the structure inversion asymmetry in the vertical direction while the miniband in the vertical direction has no Rashba spin splitting. As the space between dots increases, the Rashba coefficients decrease and the conduction-band effective mass increases. This Rashba spin splitting of the minibands will significantly affect the spin transport properties between quantum dots.