Optical Selection Rules for Hexagonal GaN

Abstract

We determined the possible symmetries for band (Bloch) states at various points of the Brillouin zone. The spin–orbit interaction has been taken into account. Free excitons offer larger sets of possible state symmetries than single carriers do. The selection rules for the optical transitions have been established. Experiments with polarized light are shown to be relevant to study the nature (s or p) of A, B, and C excitons.