Effects of an electric field on the binding energy and polarizability of shallow hydrogenoic impurity in a GaAs-(Ga,Al)As cylindrical dot

The effects of applied electric field on the binding energy and the polariz ability of a shallow hydrogenic impurity in the GaAs-(Ga,AI)AS cylindrical dot are studied within the effective mass approximation using a variational procedure for an infinite confinement potential. The binding energy and th e polarizability are calculated as a function of the radius of the cylindri cal dot for three different values of the applied electric field. Our resul ts show that the electric field tends to decrease the binding energy of the ground state, especially for large radii of the cylindrical dot and the po larizability decreases with the reduction of the dot radius. We have invest igated the polarizability as a function of the size of the structure; for o ne fixed value of the applied electric field we observed that the polarizab ility is more influenced by the quantum confinement than by the applied ele ctric field.