Soliton compression in silicon waveguides aimed at on-chip optical communication

Sydney, Australia--An international research team has for the first time produced soliton compression in a silicon photonic crystal on-chip.¹ The team hails from the University of Sydney; Tecnalia (Zamudio, Spain); Sun Yat-sen University (Guangzhou, China); and the University of York (York, England).

Andrea Blanco-Redondo and Chad Husko from the ARC Centre of Excellence for Ultrahigh bandwidth Devices for Optical Systems (CUDOS) at the University of Sydney's School of Physics led the research.

Slow-light effect
In the ideal case, soliton behavior in silicon waveguides would be similar to that of the well-studied types of solitons in an optical fiber; however, until now, however the composition and properties of silicon waveguides prevented the observation of solitons in silicon photonic crystals.

The researchers were able to compress 3.7 ps pulses of only 10 pJ energy to a 1.6 ps duration; the results were achieved using a dispersion-configured slow-light photonic-crystal waveguide.

In contrast to kilometer-scale fibers, the soliton propagation in the silicon waveguides occurs at the micron scale, due to the slow-light effect. The results could lead to miniaturization of optical components featuring soliton-based functionality in integrated silicon photonic chips.

"Our experiments will inform the ongoing push to develop optical circuits in CMOS-compatible materials such as silicon for on-chip communication, similar to the community's research in glass fiber in the 1980s," says Husko.

REFERENCE:

1. A. Blanco-Redondo et al., Nature Communications 5, 15 January 2014; doi: 10.1038/ncomms4160