UK and Spanish researchers have developed a silicon photonics multifunctional processor core employing a single hardware architecture

Researchers from the Silicon Photonics Group at the Optoelectronics Research Centre (ORC), University of Southampton, and from the Institute of Telecommunications and Multimedia Applications (iTEAM) at the Universitat Politècnica de València, have developed the first photonic integrated chip that enables multiple functionalities by employing a single common architecture.

The chip’s behaviour is similar to that seen in electronic microprocessors, where a common hardware is programmed to perform a desired operation. The team’s results have been published in the journal Nature Communications [1].

By programming the internal connections of a single chip architecture, the chip can be configured to perform different functionalities, and could be used in any field susceptible to the requirement of optical or radiofrequency signal processing, for instance self-driving cars, mobile communications, quantum computing, distributed sensors, sensing monitoring, the Internet of Things, defence, avionics and surveillance systems.

The chip architecture relies on a honeycomb waveguide mesh implemented by properly cascading tunable light couplers. The independent basic coupler configuration allows the definition of flexible interconnection schemes as well as the definition of different optical signal processing circuits.

The chip was designed by both teams, fabricated in the Southampton Nanofabrication Centre by the members of the Silicon Photonics Group, and characterised by the València team.

The main advantage of this approach is that the physical hardware architecture is manufactured independently from the targeted functionality to be performed, which reduces design cost, fabrication and testing iterations.

Once designed and tested, the chip enables the configuration of more than 100 photonic signal processing circuits, of which around 30 configurations have been demonstrated by the team in Nature Communications, resulting in the highest number reported to date.

Lead researcher of the València Group, Professor José Capmany, said: “This represents a paradigm shift in the field of integrated photonics, from application specific photonic integrated circuits to generic purpose and programmable devices, in the same way as the success experienced by the electronic field in the 80s’.â€?

Professor Goran Mashanovich, from the ORC, adds: “The chip’s complex circuit has been entirely fabricated in the Southampton Nanofabrication Centre, demonstrating the remarkable capability of our clean room.â€?

“The success of this research is also testimony to good collaboration and knowledge exchange. PhD student Daniel Perez, from the València group, spent time in Southampton during his PhD project, working with design and fabrication teams, and in particular with Dr David Thomson, Dr Li Ke and Dr Ali Khokhar. “

“We are all excited by the demonstrated circuit and look forward to extending our collaboration with València in the future.â€?

The chip was fabricated in the frame of the CORNERSTONE project that offers multi project wafer runs on different platforms to researchers in the UK and abroad.

Reference: [1] Daniel Pérez, Ivana Gasulla, Lee Crudgington, David J. Thomson, Ali Z. Khokhar, Ke Li, Wei Cao, Goran Z. Mashanovich & José Capmany. Multipurpose silicon photonics signal processor core. Nature Communications 8. doi:10.1038/s41467-017-00714-1