Key points are not available for this paper at this time.
An analytical expression of the lasing threshold for arbi trary photonic crystals was derived, which showed their reduction due to small group velocities of electromagnetic eigenmodes. The lasing threshold was also evaluated numerically for a two-dimensional photonic crystal by examining the divergence of its transmission and reflection coeffcients numerically. A large reduction of lasing threshold caused by a group-velocity anomaly that is peculiar to two- and three- dimensional photonic crystals was found.
Sakoda et al. (1999) studied this question.