Couplers enable silicon photonics

Silicon photonics can now be more efficiently connected to mainstay low index contrast fibre following a development by Chiral Photonics scientists.

The Helica TC consists of two concentric cores and a cladding. While the two cores have low index contrast, the outer core and the cladding have high contrast.

At input the low index contrast cores facilitate low-loss connectivity to standard fibres. The fibre then tapers down over its length, eliminating the inner core by the output end.

At the output end, high index contrast enables low-loss connectivity to high index contrast structures such as planar waveguides.

This interconnect exploits a dual-core fibre design to allow light from a conventional low numerical aperture fibre to be efficiently endface-coupled into another waveguide with smaller mode field dimensions and higher numerical aperture.

By permitting index-matching compounds to be used between the coupler and waveguide and eliminating the need for microlens-based coupling and air gaps, Helica affords low loss and system stable integration.

The technology supports both polarising and polarisation maintaining coupler variations.

High index contrast structures within photonic integrated circuits or planar lightwave circuits (PICs and PLCs) form the basis for a large fraction of the recent worldwide innovation in integrated optics.

Via highly efficient lasers, extremely sensitive sensors and waveguides moving vast amounts of data through small radius bends, these faster, smaller and power-conserving PICs and PLCs promise to advance everything from consumer electronics to personal computing.