And again, about lasing threshold, light localization, and density of states

We investigated numerically the relationship between the lasing threshold, the density of states (DOS), and field localization in 1D photonic crystals (PC) for off-axis laser action. The angular dependence of the corresponding quantities for the two polarizations was obtained, and it was shown that the relationship between the threshold and DOS is complex, especially near the Brewster angle in the case of p-polarization. A strong correlation between the ratio of thresholds and localizations of the two edge modes was found for s-polarization. The results of this work can be used for optimizing lasers based on one-dimensional PCs, both for normal and off-axis lasing.