Positron characteristics and positronium work function in gallium nitride under high compression

Abstract

The high-pressure effect on positron characteristics and positronium work function in GaN is investigated. The computations are essentially based on a pseudo potential approach. Our results showed that under compression the positron annihilates differently from zero pressure, its bulk lifetime decreases and the number of positronium atoms ejected from the sample into the vacuum is reduced with respect to those at zero pressure. The present study can serve as a support for future experiments of slow-positron-beam and positron annihilation in wide band gap semiconductors.