The UK’s Optoelectronics Research Centre (ORC) – one of the leading institutes for photonics research, based in the Faculty of Physical Sciences and Engineering at the University of Southampton – will announce several significant breakthroughs at Photonics West 2017, in San Francisco, between 28th January and 2nd February 2017.

A range of papers detailing the ORC’s exclusive and world-leading developments in solid state sources, the benefits of new metal-coated optical fibres and progress on novel longer wavelength fibre lasers will be presented at the renowned conference.

Professor Andy Clarkson and Dr Jacob Mackenzie gave a taste of the recent work at Southampton, to be revealed in three key papers – two at the solid-state technology development conferences, and one at the fibre lasers conference.

Scaling the power of radially-polarised beams The paper Radially polarised beam amplification in an Yb:YAG thin-slab architecture explains how it is possible to scale up the power of radially polarised beams, with benefits promised for laser cutting and materials processing.

“Our motivation here is to develop higher power laser devices,â€? Professor Clarkson commented. “Fibre lasers and solid state lasers usually have outputs that are not polarised. There are significant advantages in radially-polarised beams, which have a doughnut-shaped intensity profile, in processing applications such as fusion welding or cutting of metals.â€?

When light is incident on a metal surface, its absorption and therefore cutting speed and quality of finish depends on polarisation. The ORC’s new development is based on a slab-type architecture, which has scaling benefits for power because it has good cooling capabilities. Professor Clarkson added, “We have developed a demonstrator, based on an ytterbium-doped YAG laser to generate a wavelength of 1030nm. We have so far achieved a few watts of output but it is an architecture that we will be able to scale to very high powers.â€?

Erbium-doped YGG planar waveguide The second paper Er:YGG planar waveguides grown by pulsed laser deposition for LIDAR applications reports an erbium-doped yttrium gallium garnet planar waveguide, grown by pulsed laser deposition. The key application potential of this development is in the remote monitoring of “greenhouseâ€? gases, such as CO2 and CH4.

The technique that is used to determine amount of these gases in the atmosphere (including from an orbiting satellite) is called DIAL – differential absorption lidar. This method requires a good understanding of the absorption lines of the target gases and being able to switch the source wavelength on and off the absorption peaks. The novel ORC approach being pursued with the Er:YGG planar-waveguides is attractive, says Dr Mackenzie, because the emission lines correspond well with the absorption bands of the target gases. Pulsed output and relatively narrow spectral lines are required, which are limiting for fibre-source alternatives.

“To develop this we start with a seed-laser amplified by the Er:YGG, also based on a planar slab geometry, which again allows power scaling. Another aspect of this work, which is very important, is that at Southampton we actually grow the relevant materials ourselves in our bespoke Pulsed-Laser-Deposition (PLD) facilities.

“These waveguides are grown by PLD, which is a process of ablating a target material and the resulting plasma plume results in crystal layer growth on a heated substrate. Our team has worked out how to grow these YGG crystal layers, which has proven very difficult in bulk-crystal growth, and have the potential to work extremely efficiently as laser amplifier elements,â€? Dr Mackenzie said.

So what is the advantage of this new Southampton approach to making Er-doped YGG waveguides? Dr Mackenzie explained, “One of the sponsors of our work is NASA, who wish to use this monitoring technology in space. Our method does not only have the necessary spectral performance, but it is also scalable to the required powers for operating at earth-orbiting distances.â€?

Fibre laser development This paper Effects of coating thickness on high power metal-coated fibre lasers (Invited Paper) reports on achievements in power scaling of fibre lasers conducted at the Defence Science and Technology Group (DSTG) in collaboration with the ORC;. “The special issue here is about power scaling and effective cooling in very demanding applications such as directed energy weapons,â€? said Professor Clarkson.

“In this application you need a lot of power but with minimal active cooling to save space and minimise the total energy requirement. Everything needs to be very lightweight because it will be placed on a platform such as an aircraft. We are particularly pleased that this paper has been invited by the SPIE conference.â€?

The novelty of this work is that the fibre design has been changed. Traditional fibres for high power lasers use an outer coating of relatively low refractive index polymer cladding. A problem with traditional fibre coatings is that they tend to degrade if heated above 100deg C, which restricts their power-handling capabilities.

The new fibre design overcomes this problem by the use of an all-metal coating, so the fibre resembles a wire. It is coated with pure aluminium to replace the low-index polymer coating. This type of fibre will tolerate higher temperatures up to 400deg C.

Furthermore, the rate of cooling depends on the temperature difference with the surroundings, so at higher temperatures passive cooling becomes a lot more efficient. This in turn means its operational costs are lower and it does not require bulky cooling equipment. The aluminium-coated fibre has been demonstrated at 400deg C without optical performance degradation and output powers up to 400W. Longer-wavelength fibre lasers doped with thulium / holmium The ORC has also been developing novel optical fibres doped with thulium and holmium. The aim here is to develop fibre lasers with output powers in the multi-kilowatt regime at 2µm for a range of industrial, defence and medical applications.

Professor Clarkson commented, “Scaling two-micron fibre lasers to very high output powers will require special fibres. As with many of our breakthroughs, Southampton’s advantage is that we develop and manufacture our own fibres. This is the key to our success because we can achieve the ideal material composition with high purity to yield, low loss and high efficiencyâ€?

Meet the ORC team at Photonics West The ORC will be exhibiting at Photonics West 2017 on booth 5037, as part of the UK Pavilion in Hall D. Representatives will be based on the booth, which hosts the EPSRC-funded Future Photonics Hub, the UK’s centre for helping to link academic expertise with industry to establish a pathway to manufacture for the next-generation of photonics technologies.

Interested parties can book an appointment slot to meet with Dr John Lincoln, Industrial Liaison Manager at the show using the link: http://doodle.com/photonicshub

Download a schedule of all the ORC papers and posters at Photonics West

Transdisciplinary research, driven by expertise from Electronics and Computer Science (ECS) at the University of Southampton, has attracted global recognition for speeding the creation of intelligent autonomous systems.

The collaboration, which has successfully demonstrated unsupervised learning tasks that could be applied to powerful future devices, has been highlighted this winter in the international Nature Nanotechnology journal.

Researchers from Southampton’s Nanoelectronics and Nanotechnology research group have created a network of nanoscale devices – known as a memristors – that use unmanned machine learning protocols to observe and recognise letters of the alphabet, emulating the autonomous synoptic functions of the human brain.

The analog memristors, which have been developed with support of the EU-funded Real neurons-nanoelectronics Architecture with Memristive Plasticity (RAMP) project, have also been verified with noisy or incomplete input images.

Dr Themis Prodromakis, a Reader in Nanoelectronics at ECS and an Engineering and Physical Sciences Research Council (EPSRC) Fellow, said: “It is extremely satisfying to see the outcomes of our collaborative research programme highlighted in such a prestigious journal. The unsupervised learning demonstrated through the memristors’ image processing will have significant applications in future embedded systems used in the areas of big data and the Internet of Things.â€?

The recent Nature Nanotechnology journal highlight draws upon an article published in Frontiers of Neuroscience, entitled Analog Memristive Synapse in Spiking Networks Implementing Unsupervised Learning. The paper proposes a new analog memristor capable of pattern recognition after an unsupervised training process. These learning abilities would enable a new wave systems capable of performing tasks that would be difficult for conventional computing systems.

The International Consortium of Nanotechnologies (ICoN), led by the University of Southampton, is featured as a case study in Lloyd’s Register Foundation review of 2016, entitled "Making an Impact".

The Lloyd’s Register Foundation (LRF) is a charity that helps to protect life and property and support education, engineering-related research and public engagement. The Making an Impact review outlines the impact they’re making in becoming one of the world’s leading engineering research and education charities.

ICoN receives funding from the LRF and is featured in the Making an Impact review for its work in developing a global network to advance the application of nanotechnologies. Dr Themis Prodromakis, of the Nanoelectronics and Nanotechnology research group in Electronics and Computer Science, is the Director of ICoN and says "The support of Lloyd’s Register Foundation is key to our mission. Lloyd’s Register itself is well known for promoting safety worldwide for more than 250 years. The Foundation has become a catalyst to support research, training and education for the benefit of society. We are delighted to work alongside them.â€?

The ICoN feature appears below and the Review can be downloaded in full from the LRF website.

A global network to advance the application of nanotechnologies

Following a research call in August 2014, the Foundation funded The International Consortium on Nanotechnology (ICON) at Southampton University. ICON was awarded £3 million in 2015 with the aims of:

• developing a global capability in nanotechnology by providing partial funding for PhD studentships that address the recommendation of the Foresight review in nanotechnology, and
• establishing a research community in nanotechnology across our grant holders.

ICON, led by Dr Themis Prodromakis from the University of Southampton, has established a programme management board of experts from academia and industry to provide governance and decision making to the project.

In 2015, ICON launched its first open research call targeted at the recommendations of the Foundation’s Foresight review in nanotechnology. The ICON model is to provide seed funding for PhD studentships which must be supported by, at the least, matched funding from academia or industry.

The first call attracted 27 proposals from universities across the globe, each of which went through a rigorous peer review by leading academics before a final selection was made by the project management board. Each project was assessed on novelty of the proposed project, quality of the proposal, fit with the recommendations of the foresight review, and relevance.

ICON announced that 10 proposals had been successful from eight countries: Australia, Germany, Japan, Malaysia, Singapore, Spain, UK, and USA.

During the year, Dr Prodromakis wrote an article explaining why nanotechnology is important, Five ways nanotechnology is securing your future, for The Conversation, another of our grant recipients. The article was republished in the Guardian newspaper in the UK.

ICON announced its second call for proposals in June 2016. It is planning its first conference in April 2017 to bring together nanotechnology researchers from across the Foundation’s grant portfolio together with industry in order to showcase the nanotechnology work that is being carried out by Foundation grant holders. The conference also will also engage with industry to better understand the challenges that future ICON calls can specifically address.

The prestigious 2017 Debrett’s 500 of the most influential and inspiring people living and working in Britain today features a number of luminaries from the University of Southampton’s Faculty of Physical Sciences and Engineering, which includes Electronics & Computer Science and the Optoelectronics Research Centre.

Professor Dame Wendy Hall and Professor Sir David Payne are joined by Visiting Professor Liam Maxwell on Debrett’s list of leaders in Engineering and Technology alongside Andrew Wolstenholme, OBE, who is Chief Executive of Crossrail and a Southampton graduate.

Compiled in consultation with independent expert practitioners and commentators in each of the categories, The Debrett’s 500 was launched in 2014 to identify and celebrate the most influential people in British society. All the people in the Debrett’s 500 are scrutinised for their level of influence in shaping the lives, choices and ideas of others. Dame Wendy has featured in every Debrett’s 500 list since its launch; 2017 marks the third year running for Sir David and Maxwell on the list.

Described as ‘a leading light in the development of web services’, Dame Wendy is recognised by Debrett’s for her pioneering role as one of the first computer scientists to embark on serious research into multi- and hyper-media technologies before the existence of the World Wide Web. A Professor of Computer Science within Electronics & Computer Science, Dame Wendy also draws praise as a founding director of the Web Science Research Initiative (now the Web Science Trust) with web pioneer Sir Tim Berners-Lee, an Honorary Professor at the University of Southampton.

Sir David, Director of the University’s Optoelectronics Research Centre and Zepler Institute, features in Debrett’s for the far-reaching impact of his invention, the erbium-doped fibre amplifier – “widely regarded as one of the most important developments in modern communicationsâ€? which “facilitated the internet’s rapid growth through fast transmission and amplification of large amounts of data.â€?

A Visiting Professor within Electronics and Computer Science, Liam Maxwell became the UK’s first national technology adviser in 2016 after serving as the government’s Chief Technology Officer. He is credited with the digital transformation of the UK government.

Baroness Martha Lane-Fox of Soho, Chair of the digital skills charity Go ON UK and recipient of an Honorary Doctorate of Science from the University of Southampton, features on Debrett’s list of the UK’s Digital & Social leaders. Baroness Lane-Fox, co-founder of the successful website lastminute.com, has worked for many years to help make the UK the most digitally-skilled nation in the world.