New research to assess how lasers may provide more energy-efficient Internet

Posted on: 21 February 2017

Professor John Donegan from Trinity's School of Physics has been awarded €1.46m through Science Foundation Ireland’s Principal Investigator scheme to investigate how laser technology could deliver more energy-efficient devices for future optical networks.

This will potentially lead to exceptionally fast broadband. This research is thus of particular interest to the ICT sector and Nokia Bell Labs have a keen interest in the project as the energy-efficient devices being examined will likely complement the collaborative research activities they are currently undertaking with Professor Donegan’s team.

Optical networks use light to transmit information and are a critical part of the world’s Internet infrastructure. These optical networks currently use about 1% of the world’s total electricity supply, but the growth rate is immense and projections suggest it could reach 5% by 2022. For this reason, there is an urgent need to tackle the energy requirements of communications networks.

Professor Donegan’s research will examine the individual semiconductor lasers that currently light up global optical networks and will attempt to develop lasers that can operate at a range of temperatures without changing wavelength – one of the main contributing factors to energy usage in optical networks. Professor Donegan’s approach is unique in this research field.

Professor Donegan, commenting on the award, said: “The world as we know it depends critically on the wired internet for communications. Each day, billions of e-mail and webpages traverse the net and there is a substantial cost in operating this network. A major impediment to growth in the future is the electrical power required to operate the net. Our research will investigate a range of new laser structures that operate with much improved efficiency and I look forward to further testing our devices with industry.

“These lasers are quite efficient, but still require an in-built cooling system to keep the laser at a precise wavelength. Since hundreds of lasers operate on the network, they cannot be allowed to shift wavelength when they operate. The challenge therefore is to develop lasers that are "athermal", i.e. operate at a range of temperatures but do not change wavelength. This is the research challenge that we will address with this funding. The research team will also look at a range of different semiconductor laser structures and work on the integration of new materials sets, coupling semiconductors, oxides and polymers, into the standard materials for optical communications lasers.”

Professor Donegan is an Investigator in two Science Foundation Ireland research centres in Trinity: AMBER, the materials science research centre, and CONNECT, the centre for future networks and communications. This award, which will benefit both centres, will run until 2022 and will support a team of five researchers: two post-doctoral researchers and three graduate students.