Electric field effect in a GaAs/AlAs spherical quantum dot

Using a variational procedure within the effective-mass approximation we calculate the binding and normalized binding energy (NEbF) of a shallow donor impurity in a GaAs/AlAs spherical quantum dot, under the action of constant uniform electric field applied in the z-direction. A proper choice of the dot radius and electric field can largely change NEbF of a centre shallow impurity in the spherical quantum dot, which may be used to feel the small change in the dot radius.