Theoretical characterization of carrier compensation in P-doped diamond

Based on the electron-hole recombination ratio (the number of electron-hole recombination in unit time and volume), we have examined several P complexes surrounded with vacancy (V) or H to explore the effect of carrier compensation on the electronic properties in P-doped diamond by first-principle calculations. Our calculated results show that the monovacancy complex P-V-H is not a valid recombination center in P-doped diamond, in which case electron cannot be recombined and thus donor cannot be compensated. However, the level in the band gap introduced by the divacancy complex P-2V-2H is a valid recombination center, which accelerates the electron-hole recombination at high ratio. For the trivacancy complex P-3V, three levels are introduced near the middle of the band gap, which may serve as more valid recombination centers than others. In this case, the electron-hole recombination ratio enhances successively, namely, the compensator density increases continuously too. In addition, the electronic properties of the P-related complexes in negative charge states are similar with those of neutral charge states. The study may explain well the experimental results and be useful for the further experiment research.