Fastest Switch Yet

Trellis Photonics, a Columbia, MD-based technology company, has achieved sub-microsecond photonic switching speed, claimed to be the fastest optical speed to date. The breakthrough was accomplished through the company’s patented ‘Electroholography’ technology and demonstrated at the National Fiber Optic Engineers Conference in the US.

‘The ability of Electroholography to achieve this switching speed demonstrates the technical superiority of a solid state switching device over other technologies,’ said Tim Cahall, Trellis Photonics’ CEO.

Electroholography (EH) is a beam stirring method based on reconstructing volume holograms by means of an externally applied electric field. EH exploits the voltage controlled photo-refractive effect at the paraelectric phase. Volume holograms stored as a spatial distribution of space charge in a paraelectric crystal can be reconstructed by the application of an electrical field to the crystal. This field activates pre-stored holograms, which determine the routing of light beams.

‘The inherent speed of Electroholography makes our Intelligent Lambda Switch (ILS) the fastest photonic switch in the world,’ added Cahall.

The ILS will be used to build all-optical crossconnects (OXCs) and optical add & drop multiplexers (OADMs) with capabilities to monitor and manage each channel in a DWDM system.

Dense Wavelength Division Multiplexing (DWDM) systems have been developed as a way to maximise the capacity of existing fibre-optic infrastructure. Whereas initial fibre-optic technology enabled only one wavelength to be transported over a fibre, DWDM technology is based on the use of varying wavelengths to conduct groups of signals over the same fibre.

There are two critical interconnecting elements in DWDM networks – optical crossconnects (OXC) and optical add & drop multiplexers (OADM). The OXC is responsible for determining the routes of all DWDM channels on multiple fibers between the networks. OADM is used for routing a subset of the channels on a single fibre.

The Intelligent Lambda Switch, a key component of such systems, will be available in the second quarter of next year.

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