Electro Absorption Modulation: Basics and Applications

This lecture covers the electro absorption modulation based on the Franz Keldysh effect, where an applied electric field alters the absorption coefficient. It explains the red shift in the absorption band edge and the concept of transmittance in EA modulators. The instructor discusses the materials and structures used in EA modulators, emphasizing the advantages such as the ability to operate at zero bias voltage and integration with semiconductor lasers. A comparison between EA modulators and MZI modulators is presented, highlighting the benefits of EA modulators in terms of voltage requirements, polarization independence, integration capabilities, compactness, and cost-effectiveness.