Characteristics of a Photonic Bandgap Single Defect Microcavity Electroluminescent Device

A microcavity surface-emitting coherent electroluminescent device operating at room temperature under pulsed current injection is described. The microcavity is formed by a single defect in the center of a 2-D photonic crystal consisting of a GaAsbased heterostructure. The gain region consists of two 70Å compressively strained In0 15Ga0 85As quantum wells, which exhibit a spontaneous emission peak at 940 nm. The maximum measured output power from a single device is 14.4 W. The near-field image of the output resembles the calculated TE mode distribution in a single defect microcavity. The measured far-field pattern indicates the predicted directionality of a microcavity light source. The lightcurrent characteristics of the device exhibit a gradual turn-on, or a soft threshold, typical of singleor few-mode microcavity devices. Analysis of the characteristics with the carrier and photon rate equations yields a spontaneous emission factor 0 06.