Positron behaviour in GaSb under pressure

The independent particle model was used to compute the pressure effect on positron states in GaSb in the zinc-blende structure. The positron energy levels and wavefunctions at different points of the reciprocal space at normal and under hydrostatic pressure are calculated. An illustrative result of positron thermalization energy and effective band mass shows that the pressure effect manifests by the decrease of both these quantities which tells us that the positron diffuses better under pressure. The positron charge density is reduced under pressure at the interstitial positions and slightly increased at the inter-nuclear spacing. This theoretical estimation is essential for studying positron annihilation in semiconductors under pressure. (C) 1999 Elsevier Science Ltd. All rights reserved.