Tuneable Coupling Structures for Integrated Silicon Photonics

• Applicant: Professor Dr.-Ing. Manfred Berroth
• Subject Area: Electronic Semiconductors, Components and Circuits, Integrated Systems, Sensor Technology, Theoretical Electrical Engineering
• Term: from 2013 to 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 252274958

Commercial optical transmission systems achieve data rates of 100 Gb/s on a single wave length. Future systems are targeting for data rates of more than 1Tb/s with advanced modu-lation schemes. Therefore, highly efficient photodetectors are required at the receiver side. At the INT non-periodic grating couplers with a record coupling efficiency of -0,62 dB have been achieved with an optical -1dB bandwidth of 40 nm. In the previous DFG project BE2256/23-1 a shifting of 44.7 nm is achieved for the peak envelope of the coupling effi-ciency of a periodic grating coupler. The variation of the peak of the coupling efficiency is investigated by applying the electrooptic effect in a p-n-configuration as well as the ther-mooptic effect. As the thermooptic change of the refractive index is more pronounced, a pure p-or n-doped silicon guiding layer is proposed here. Using the thermooptic effect, a non-periodic grating coupler with backside mirror is suggested with minimum electrical power consumption. The non-periodic grating shall be optimized for a broad coupling range. Finally polarization splitting will be investigated by two-dimensional grating couplers.

• DFG Programme: Research Grants