Vertical cavity surface emitting lasers as sources for optical communication systems: A review

Next generation integrated photonic circuits will be dominated by small footprint devices with lower power consumption, low threshold currents and high efficiencies. Vertical Cavity Surface Emitting Lasers (VCSELs) having those attractive qualities has shown results to meet the next generation demands for optical communication sources. VCSELs applications are sensors, data com, optical communication, spectroscopy, printers, optical storage, laser displays, atomic optical clocks, laser radar, optical signal processing to name a few. This review centres around on the basic operation of semiconductor lasers, structure analysis of the devices and parameter optimisation for optical communication systems. This paper will provide comparisons on growth techniques and material selection and intends to give the best material realisation for nano optical sources that are up to date as used in optical communication systems. It also provides summarised improvements by other research groups in realisation of VCSELs looking at speeds, efficiency, temperature dependence and the device physical dimensions. Different semiconductor device growth methods, light emitting materials and VCSELs state of art are reviewed. Discussions and a comparisons on different methods used for realising VCSELs are also looked into in this paper.