EFFECT OF THE IMAGE POTENTIAL ON THE STARK SHIFT OF EXCITON-STATES INA QUANTUM-WELL

We consider the image potential and its effect in calculating the bind ing energy of the ground bound state of an exciton in a finite quantum well subjected to an external electric field by means of the variatio nal technique. The influence of the image potential is obtained as a f unction of the well width, the electric-field strength, and the ratio of the dielectric constants of different media. It is found that the i mage-potential effect will give significant corrections to the exciton binding energy and its Stark shift. The self-image potential and mutu al-image potential have opposite effects on the Stark shift.