Optimization of dressed-photon–phonon-assisted annealing for fabricating GaP light-emitting diodes

Using the two-level two-state model, we analyzed the characteristics of enhanced electroluminescence intensity from a GaP LED fabricated by dressed-photon–phonon-assisted annealing. In this model, we utilized the fact that the adiabatic potential barrier of the electronic excited level in configuration space is lower than that of the ground level. It was confirmed by experiments that, in an actual excited level, the barrier was reduced to 0.48 eV. From this finding, it was shown that the spatial distribution of Zn atoms can be changed by means of current injection and light irradiation even at room temperature. In addition, we showed that a structure that is suitable for light emission via DPPs is formed by means of a transition between a low-barrier excited level and a high-barrier ground level, due to stimulated emission. Also, regarding the optimized conditions for maximizing the effect of DPP-assisted annealing, it was found that the optimum ratio of the number of injected electrons to the number of irradiated photons is close to 1, and this was confirmed experimentally.