Researchers develop photonic chips that speed-up networks

Dr Amol Choudhary (left) and Sydney Nano Director Professor Ben Eggleton in one of the photonics labs at the Sydney Nanoscience Hub. Photo by Louise Cooper. Source: sydney.edu.au.

University of Sydney scientists have developed a chip that speeds up the time required for the transfer of digital information.

With an ever-expanding volume of data now being sent around the world on the internet via fibre optic networks, increasingly complex digital signal processing and laser-based ‘local oscillator’ systems are needed to transfer photonic information and transfer it into the electronic information that computers can process.

The chip-based information recovery technique developed by the University of Sydney research team eliminates the need for these separate laser-based local oscillators and complex digital signal processing systems, speeding up data transfers.

“Our technique uses the interaction of photons and acoustic waves to enable an increase in signal capacity and therefore speed,” said Dr Elias Giacoumidis, the joint lead author of a new research study.

“This allows for the successful extraction and regeneration of the signal for electronic processing at very-high speed.”

Incoming photonic signals are processed in a filter on a chip made from chalcogenide glass, which has acoustic properties that enables photonic pulses to ‘capture’ incoming information and transport it to the chip for processing into electronic information.

Dr Amol Choudhary said that the technique, involving a process known as stimulated Brillouin scattering, has produced a record-breaking narrowband of about 265 megahertz bandwidth for carrier signal extraction and regeneration.

“This narrow bandwidth increases the overall spectral efficiency and therefore overall capacity of the system,” Dr Choudhary said.

Choudary said the technology can increase processing speed by microseconds. “While this doesn’t sound a lot, it will make a huge difference in high-speed services, such as the financial sector and emerging e-health applications,” he said.

The research team’s next step will be to construct prototype receiver chips for further testing.

Ben Eggleton, group research leader and director of Sydney Nano, said that the technology’s capacity to improve transfer speeds would provide benefits for many industries.

“The fact that this system is lower in complexity and includes extraction speedup means it has huge potential benefit in a wide range of local and access systems such as metropolitan 5G networks, financial trading, cloud computing and the Internet-of-Things,” Eggleton said.