Abstract

Quantum-well lasers that rely on a separate-confinement-heterostructure design to achieve confinement suffer performance limitations due in large part to the dynamics of the carrier-transport mechanisms. This obstacle has prompted researchers to investigate alternative current-injection mechanisms by modifying the injection region. To date, most efforts in this area have concentrated on designs with graded or short injection layers. One group has suggested employing a tunneling scheme in which carriers tunnel from an injection well into a second well where the lasing transition occurs. In this manner many of the adverse effects associated with high injection currents can be avoided, resulting in enhanced device characteristics including higher modulation band widths.^1,2

© 1995 Optical Society of America