Photonic bandedge lasers in two-dimensional square-lattice photonic crystal slabs

Square-lattice bandedge lasers are realized by room-temperature optical pumping of photonic crystal air-bridge slabs of InGaAsP quantum wells emitting at 1.5 mum. Lasing modes corresponding to the second bandedges near the X and M points are identified from their spectral positions and polarization directions. A low threshold incident pump power of less than 1 mW is achieved for the laser operating at the second bandedge near the X and M points, with only 15x15 lattice points. The measured characteristics of the bandedge lasers closely agree with the result of calculations based on the plane-wave-expansion method and the finite-difference time-domain method. (C) 2003 American Institute of Physics.