Optical signal processing device provides ‘unprecedented’ level of control

The team says the device can meet the demands of high capacity optical networks and has a range of applications such as ultrafast optical measurement and sensing. According to Professor David Richardson, who led the project at the University of Southampton's Optoelectronics Research Centre, pictured, the device is reconfigurable and was created to automatically tune the phase properties of ultrafast light signals. The phase quantisation is said to be similar to the way electronic circuits can adjust electrical signals to ensure voltage matches the discrete set of values required for digital computing. Prof Richardson says this is a significant breakthrough as the device allows an unprecedented level of control and flexibility in processing light using light. "Today parametric mixers are routinely used for laser wavelength conversion, spectroscopy, interferometry and optical amplification," he said. "Conventional parametric mixers when operated in a phase sensitive fashion have for many decades been known to have a two level response. We have now managed to achieve a multilevel phase response which means that we have demonstrated for the first time, a device that squeezes the classical characteristics of its input light to more than two phase levels." The researchers claim to have used the device to remove noise picked up by a signal during transmission in optical fibre at over 100Gbit/s. They believe that this can be done even faster, at speeds hundreds of times greater than could be achieved using electronics and using less power. The research is part of the European Union Framework 7 PHASORS project which completed earlier this year.