Optical and high speed characterisation of Vertical Cavity Surface-Emmiting Lasers for Optical Interconnects

Student: Dakshita Senaratne

Supervisor: Aleksandar Rakic

Category: Engineering Thesis Project - Communications

The possibility if replacing electrical lines and connectors with optical interconnections at all levels (especially in high performance digital systems) is currently a topic of great research interest. As clock speeds increase, optical connections are expected to provide advantages such as higher frequencies, high interconnection density as well as reducing cross talk, power dissipation and clock skew.

Like all optical systems, optical interconnections can be broadly partitioned into a transmitter, channel and receiver. Technologies of implementing optical interconnects in high speed digital systems together with possible technologies for the transmitter are in active research interest. The ‘Smart Pixel’ technology has formed a great part of the research on implementation technologies. Transmitter characteristics such as low bean divergence and low power dissipation are critical for optimized performance and one particular transmitter- VCSEL, has been identified as the best solution .

In order to understand the full application of VCSELs in optical interconnects and their performance under different conditions, they need to be characterized. Specifically, this includes its power, spectrum, light-current characteristics and beam profile. The limiting factors of their application to optical interconnects can then be identified.

This thesis explores the characteristics of a VCSEL including Light-current, power and spectrum characteristics and details parameter extraction techniques. Finally several parameters of the VCSEL are extracted.

Thesis Document (PDF)