Photonic Integrated Circuits

Optical communication networks have grown at a phenomenal rate since the introduction of commercial optical systems in 1980s, with capacity nearly doubling every year. One of the main driving factors has been the advancement in multichannel wavelength division multiplexed (WDM) optical systems which have significantly extended the accessible bandwidth of the optical fiber. This book, written in the form of a thesis, demonstrates the key role played by photonic integrated circuits (PICs) in WDM systems by making them simpler, smaller, cheaper, and more versatile. It takes the reader through different stages of creation of a PIC: conceptualization, design, epitaxial growth, fabrication and testing. Using such PICs, a coherent optical RF link is built which clearly shows the advantage of photonic integration over discrete element systems. Ultimately, using the principles of photonic integration, a monolithically integrated reconfigurable optical add-drop multiplexer (MI-ROADM) is demonstrated which has the potential to further revolutionize WDM systems.