Very-low-threshold photonic band-edge lasers from free-standing triangular photonic crystal slabs

Abstract

Photonic band-edge lasers are realized in the free-standing triangular photonic crystal slab with InGaAsP quantum wells at 80 K. Surface-emitting lasing actions are observed from the samples whose wavelengths correspond to the second or the third photonic band edge near the Gamma point of the band structure, which is confirmed by the three-dimensional finite-different time-domain calculation. A very low threshold of 35 muW (incident pump power) is achieved from the laser operating near the third transverse-electric-mode band edge. This low threshold is benefited from low optical losses near the Gamma point as well as reduced surface recombination carrier losses and enhanced material gain at low temperature. It is interesting to note that this two-dimensional distributed feedback lasing action is observed from a surprisingly small pump area of 6 mum in diameter. (C) 2002 American Institute of Physics.