Theoretical calculations predicted that the concentration of interstitial Li could be decreased. That is, the Li acceptor, LiZn, could be stabilized by above-bandgap photo-irradiation. The creation of excess electrons by irradiation increased the occupation probability of the Lii donor level, and therefore the concentration of Lii°. Consequently, the LiZn concentration increased via the reaction, Lii° + VZn°  LiZn, where VZn and LiZn were a neutral Zn vacancy and a neutral Li acceptor, respectively. It was concluded that Li acceptors would tend to be stable in the active regions of light-emitting and laser diodes.

M.Ichimura, T.Wada, S.Fujita, S.Fujita: Journal of Applied Physics, 1993, 73[11], 7225-8