Hydrostatic pressure effect on the donor impurity states in asymmetric multiple quantum wells

Based on the effective-mass approximation, hydrostatic pressure effect on the donor binding energy in zinc blende (ZB) InGaN/GaN asymmetric multiple quantum wells (AMQWs) is investigated variationally. Numerical results show that the hydrostatic pressure increases the donor binding energy for any impurity position. Moreover, the hydrostatic pressure effect is more noticeable if the impurity is localized inside the wide well of the AMQWs. For any hydrostatic pressure, the donor binding energy is distributed asymmetrically with respect to the center of the AMQWs. In particular, the donor binding energy of impurity located at the center of the wide well of the AMQWs is insensitive to the increment of the inter-well barrier width if the inter-well barrier width is large. (C) 2010 Elsevier Ltd. All rights reserved.