Integrated solutions for optical orbital angular momentum multiplexed transceiver

• Applicant: Professor Dr.-Ing. Dirk Plettemeier
• Subject Area: Electronic Semiconductors, Components and Circuits, Integrated Systems, Sensor Technology, Theoretical Electrical Engineering
• Term: from 2019 to 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 405632792

The proposed project deals with integrated solutions for optical orbital angular momentum (OAM) multiplexed transceivers. This kind of transmission technology is an attractive way to further enhance the capacity of optical communication systems.During the last decade, the capacity of single optical fiber was increased by exploiting coherent transmission combined with advanced modulation formats (DP-QPSK, QAM) and the transition from the standard DWDM frequency grid to optical superchannels. However, the transmission capacity of standard optical fiber itself tends to be restricted by the nonlinear Shannon limit. To overcome that bottleneck, optical communications based on the Spatial Division Multiplexing (SDM) has attracted significant research interest. Being free to choose the basis of fiber modes working as orthogonal signal carriers for MDM transmission, it is sensible to use the basis of vortex modes. They offer high mode conversion efficiency at the (de)multiplexer compared with the other modal bases.Currently, generation, modulation and detection of optical vortices are provided by bulk optical devices. The effective involvement of OAM-based transmission techniques into industrial applications requires robustness and repeatability, which is difficult to achieve with discrete components. Hence, the development of the compact integrated optical components, capable of on-chip generation, transmission and processing of optical vortices, is the next key step towards robust and energy- and cost-effective OAM-based information systems and to the involvement of this data multiplexing technique to the short-range scenarios. Moreover, the fabrication process of such components should be compatible with the existing lithography and micromachining techniques.In order to provide integrated transmitter and receivers, key components such as the spatial multiplexer / demultiplexer (SMUX) shall be realized as photonic integrated circuit in industrially available manufacturing processes. Electronic-photonic integrated circuits (EPIC) allow the co-integration of these (passive) photonic circuits and high-speed electronics like photodiodes and possibly trans-impedance amplifiers based on SiGe technology. Thus, the main challenge of the proposed work is the effective realization of the devices based on photonic integrated circuits.We propose to develop a transmitter based on integrated OAM emitter and a fully integrated on-chip receiver. The appropriate design approach will be determined in accordance with the analysis of available manufacturing platforms and detailed simulations of possible integrated microstructures. The produced integrated devices will be characterized experimentally to confirm their functionality, defined by the analytical and numerical models. Moreover, system-level experiments with the CW optical signal and the modulated telecommunication signals of different modulation formats will be provided.

• DFG Programme: Research Grants
• International Connection: Russia
• Partner Organisation: Russian Science Foundation
• Cooperation Partner: Professor Dr.-Ing. Albert Sultanov