WDM is a key technology for increasing the data rate in optical communications systems, which currently incorporate large electro-optic modulators/detectors, multiple lasers and complex multiplexer circuits. Consequently large electrical power is consumed and, as such, on-chip integration is prohibited.
Our novel, energy efficient photonic crystal technology WDM architecture can be used both for ultra-high speed on-chip optical interconnects and in active optical cables. Our architecture consists of a single multi-wavelength laser and highly wavelength selective modulators and photodetectors.
An optical waveguide is placed vertically on top of all the modulators and detectors to carry all the channels inside the transmitter and receiver section. At the transmitter end, individual channels are modulated by serially-placed modulators while propagating through the waveguide and then transmitted by an optical fibre to the receiver end.
This architecture eliminates the necessity for complex multiplexer and de-multiplexer circuitry. The photonic crystal technology based devices are 100 times smaller than those used in conventional architectures, thus promising a very high channel scalability and their power consumption can be three orders of magnitiude smaller than in conventional devices. Our unique WDM architecture can combine hundreds of such channels, thereby promising to offer a terabit/s transmission link for both on-chip optical interconnects and active optical cables.
UK patent application 1113125.7.
Published as WO2013/017814 on 7 February 2013
National phase patent applications in USA, Canada, EU and India.