Quantum-Dot Surface Emitting Distributed Feedback Lasers Using Indium-Tin-Oxide as Top Claddings

Abstract

We demonstrate InAs/InGaAs quantum-dot surface emitting distributed feedback (SE-DFB) lasers, using an indium-tin-oxide layer as top cladding, which eliminates the regrowth process used in conventional DFB lasers to greatly simplify laser process. The lasing peak near 1.30 mu m realized using the grating period of 375 nm exhibited a 0.13-nm linewidth and a low-temperature red-shift rate of 0.1 nm/K. The laser had a threshold current density of 210 A/cm(2) and a characteristic temperature of 94.6 K. The surface emitting laser light had the divergence angles of less than 1 degrees and 8 degrees similar to 9 degrees along and perpendicular to the grating direction, respectively.