The HELIOS European Project team demos high speed slow light-enhanced electro-optical modulators

GRENOBLE, FRANCE: CEA-Leti, co-ordinator of the European HELIOS project to accelerate commercialization of silicon photonics, unveiled a 40Gbit/s optical modulator in silicon with a record extinction ratio of 10dB developed by the HELIOS Project members.

In an effort to push forward this state-of-the art technique, an ultra-high speed optical modulator enhanced via “slow light” propagation has now been demonstrated. Slow light propagation is referred to when light travels significantly slower in a modulator than it does through air or in a vacuum.

The attractive properties of slow light propagation in a nanostructured 1D periodic waveguide, together with a high speed semiconductor pn diode were exploited to demonstrate a highly efficient 500 µm-long silicon electro-optical modulator device, exhibiting modulation rate capabilities reaching 40 Gbit/s.

Further, using a dual-drive modulation scheme would enable the integration of the developed optical modulator with electronic BiCMOS logic circuitry. These results are a major breakthrough in the field and offer a unique opportunity to bridge the mismatch in size and power requirements between advanced CMOS-electronics and current silicon optical modulators.

The 325 square micron device, built in a CMOS-compatible process by the CEA-Leti, coordinator of the HELIOS Project, is the result of a close collaboration between the Valencia Nanophotonics Technology Center at Universitat Politecnica de Valencia (Spain) and the Silicon Photonics Group at the Advanced Technology Institute, University of Surrey (UK).

HELIOS' partners have unveiled these results in Optics Express, Vol. 19, Issue 21 and during the 8th International Conference on Group IV Photonics in London (UK) on September 14th-16th 2011, at the prestigious post-deadline session.