Nondegenerate monopole mode of the single-defect two-dimensional triangular photonic band gap cavity

Summary form only given. The use of a single-defect photonic band gap (PBG) cavity offers the possibility of spontaneous emission modification and nearly thresholdless laser operation. Recently, Caltech group demonstrated a single-defect PBG laser based on a dipole defect mode of two-dimensional (2D) triangular lattice. In this work, we propose and characterize a nondegenerate 2D monopole mode instead of the degenerate dipole mode as a candidate for a thresholdless PBG laser.