Timo Aalto leads the Silicon Photonics research at VTT. His research focuses on the micron-scale silicon waveguides that are used to make ultra-compact and low-loss photonic integrated circuits for communication, imaging and sensing applications at near and mid infrared wavelengths. He has contributed to about 100 scientific publications, reviewed several EU projects, journal articles and theses and coordinated large projects funded by Business Finland, EU, the European space agency and industry. Timo Aalto received his D.Sc. (tech) degree in optoelectronics technology from the Helsinki University of Technology in 2004 and has worked in Silicon photonics research at VTT since 1997.
Polarization-independent photonic integrated circuits (PIC) can be realized with 3 µm silicon-on-insulator (SOI) waveguides that offer a combination of ultra-low losses and dense integration. A short overview of this technology is presented and followed by some recent examples of hybrid integration and packaging. In particular, III-V light source integration can be used for amplification and lasing at near and mid infrared wavelengths. Low-loss, polarization independent and ultra-broadband fiber coupling can be achieved with either polished interposers or polymer lenses. Also a few application examples are provided for this technology.
Recently Silicon Photonic foundries have been incorporating InP building blocks in their PDKs. Industrial efforts from Tower Semiconductor, SCINTIL photonics, Skorpios, and Global Foundries should be highlighted. In parallel, we have seen advances in new on-chip modulators- plus the new materials to make them. For example, Lithium Niobite from Hyperlight or Ori Chip, Polymer-based modulators from Lightwave Logic, NLM Photonics or Sylorix, plasmonics from Polariton or developments Lumiphase made with BTO materials. The list of companies is increasing fast.