J.K. Kim

Abstract: Semiconductor lasers emitting at 1.55 μm with external differential efficiencies >1 have been created by monolithically connecting several active regions in series within a single optical waveguide. This is accomplished by epitaxially stacking a number of p–i–n multiquantum well active regions with intermediate n++–p++ back diodes, which enable the entire terminal current to flow through each active region stages in series. Such lasers should also improve the impedance match as well as provide for low-noise, high-efficiency microwave links.

TL;DR: In this article, an all-monolithic, single-step grown, room-temperature, electrically-pumped vertical cavity laser based on III-As compounds is presented with a threshold current density 570 A/cm/sup 2, a differential efficiency greater than 50% and a threshold voltage of 3 V.

TL;DR: In this article, a lattice-matched 1.55μm vertical-cavity surface-emitting laser operating continuous wave up to 88°C was demonstrated. But the performance of the laser was limited by the poor electrical and thermal conductivity of these mirrors, circumvented by utilizing an InP double-intracavity contacted structure.

TL;DR: In this paper, a bipolar cascade vertical-cavity surface-emitting laser with a greater-than-unity differential quantum efficiency (WQE) of 1.55 μm was presented.

TL;DR: In this article, the authors investigate QD active material in which lateral diffusion is intentionally reduced, and they demonstrate reduced lateral diffusion in the material with which they expect >50% reduction in the threshold current for 1-μm wide edge emitters or 5μm-diam VCSELs.