Abstract

Vertical-cavity surface-emitting lasers (VCSELs) have emerged as important light sources for the data communication, optical interconnects, and optical storage. Higher output power (> 3 mW) and stable single-fundamental mode operation is very desired for many applications, such as free-space reading/writing in the storage system, and optical link in one- and two-dimensional interconnects. We may define the stable single-fundamental mode operation as a lasing that can maintain single-fundamental mode emission over the entire drive current range above the threshold. Although various device structures have been attempted, including the proton-implant and oxide confined VCSELs, only few can exhibit both high power and stable single-fundamental mode operation.^1,2 To obtain a stable single-fundamental mode operation, usually the active region of the VCSELs required to be less than 5 µm diameter^1,2 formed by either proton-implant or oxidation. Since the active region of the single mode VCSELs is usually small resulting in a large series resistance and serious ohmic heating, which in turn limits the maximum drive current and the output power of the devices. In this letter, we report that a VCSEL with a 10 × 10 µm² active region confined by proton-implant and a 5 × 5 µm² absorber aperture formed by zinc diffusion exhibited a stable single fundamental mode emission³ with a maximum power of 3.2 and 4.4 mW at room-temperature and –7°C respectively. The active region with a larger area allowed more current injection resulting a high output power, while the absorber suppressed the higher-order mode and maintained a stable single-fundamental mode operation over the entire drive current range.

© 2002 Optical Society of America