40.1-GHz sub-freezing 850-nm VCSEL: microwave extraction of cavity lifetimes and small-signal equivalent circuit modeling.

We present an 850-nm vertical-cavity surface-emitting laser (VCSEL) constructed for a wide operating temperature range from 25°C to -50°C sub-freezing temperature, demonstrating 40.1-GHz at -50°C. The optical spectra, junction temperature, and microwave equivalent circuit modeling of a sub-freezing 850-nm VCSEL between -50°C and 25°C are also discussed.

29 GHz single-mode vertical-cavity surface-emitting lasers passivated by atomic layer deposition.

The fabrication processes of high-speed oxide-confined single-mode (SM)-vertical-cavity surface-emitting lasers (VCSELs) are complex, costly, and often held back by reliability and yield issues, which substantially set back the high-volume processing and mass commercialization of SM-VCSELs in datacom or other applications. In this article, we report the effects of AlO passivation films deposited by atomic layer deposition (ALD) on the mesa sidewalls of high-speed 850-nm SM-VCSELs. The ALD-deposited film alleviates the trapping of carriers by sidewall defects and is an effective way to improve the performance of SM-VCSELs.

Investigation of the current influence on near-field and far-field beam patterns for an oxide-confined vertical-cavity surface-emitting laser.

This experiment presents dynamic behaviors between the operating current and the optical beam images of vertical-cavity surface-emitting lasers (VCSELs) with two different aperture diameters of 3 µm (single-mode) and 5 µm (multi-mode). These VCSELs exhibit complex optical phenomena under current injection such as thermal effects, modal competition, carrier distribution, and laser coherence which make the light field distribution difficult to predict. In this report, the DC properties, optical spectrum, and optical images were measured together at different operating currents to accurately evaluate the characteristics of the lasers.

High-frequency performance of submicrometer transistors that use aligned arrays of single-walled carbon nanotubes.

The unique electronic properties of single-walled carbon nanotubes (SWNTs) make them promising candidates for next generation electronics, particularly in systems that demand high frequency (e.g., radio frequency, RF) operation.