Monolithic integrated reflective transceiver in indium phosphide

Abstract

The work presented in this thesis is about an InP based monolithic integrated reflective transceiver meant for use in future fiber access networks at the user site. The motivation for this research results from the users’ demands for ever-increasing bandwidth at low cost of operation, administration and maintenance. We investigated solutions to these challenges with a network concept using a dynamically reconfigurable optical network topology with a wavelength router and a colorless optical network unit. This work focuses on developing the optical part of the optical network unit, a reflective transceiver. This reflective transceiver consists of three basic components: a tunable wavelength duplexer, a photodetector and a reflective modulator. The tunable wavelength duplexer separates two wavelengths, one for the downstream and one for the upstream signals, and guides them to the photodetector and the reflective modulator. The photodetector detects the downstream data. The reflective modulator modulates the light carrier with the upstream data and reflects it back to the network. The integrated transceiver was realized bymonolithically integrating these components on a common active-passive butt-joint layer stack based on InP technology. This approach not only offers high bandwidth for both downstream data and upstream data, but also lowers the cost of the device and the network operation because of the colorless operation at the user site. The main results obtained within this work are summarized as follows: an efficient and polarization insensitive tunable wavelength duplexer was realized; a new method to fabricate a reflective SOA has been proposed and demonstrated; a high performance waveguide photodetector based on SOA layer stack was successfully fabricated; a low cost photoreceiverwhich includes an InP photodetector and a SiGe amplifier was demonstrated; aworking monolithic integrated reflective transceiver based on InP was successfully realized and demonstrated; two monolithic integrated transceivers aiming for higher bandwidth have been designed and fabricated. In addition, a novel MMI reflector has been proposed and realized with high reflectivity. This work was funded by DutchMinistry of Economic Affairs through the Freeband Project Broadband Photonics Access, the Smartmix projectMemphis and the NRC Photonics