An ab initio pseudopotential calculation of ground-state and excited-state properties of gallium nitride
Published in J. Phys.: Condens. Matter 6, 8781 (1994)
Semiconductor Physics Group, Department of Physics, University of Exeter, Stocker Road, Exeter EX4 4QL, United Kingdom
(received 31 May 1994, in final form 4 August 1994)
In this work, the electronic, ground-state and vibrational properties of both alpha-GaN (i.e. wurtzite structure)
and the recently fabricated beta-GaN (i.e. zincblende structure) have been studied using the ab initio
pseudopotential method within the local density approximation and a simple quasiparticle scheme. The calculated
equilibrium lattice constants, bulk moduli, the pressure derivatives of the bulk moduli, and the A1 TO(gamma)
phonon frequency are in good agreement with available experimental and other recent ab initio theoretical
results. The self-energy band gap corrections are found to be highly k-dependent. The calculated fundamental band gap
is direct in both cases and for the experimental lattice constant is calculated to be 3.36 eV in beta-GaN and
3.48 eV in alpha-GaN, in excellent agreement with experiment.
Stephen Jenkins
Last modified: Mon Mar 4 14:29:30 GMT 1996