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A team of physicists from the SFI funded AMBER (Advanced Materials and BioEngineering Research) Centre at Trinity College, Dublin have made a new device which could lead to a breakthrough in mass storage of digital data. Two PhD students, Yong Chang Lau from Malaysia and Davide Betto from Italy, working with senior researcher Dr Karsten Rode and Professors Michael Coey and Plamen Stamenov published their results in the prestigious journal Nature Nanotechnology earlier this Summer [1].

Professor Michael Coey, a Principal Investigator in AMBER and the School of Physics, Trinity College Dublin, said, ‘The flood of digital data is growing every year and new storage concepts are urgently needed to sustain the information revolution. Forecasts envisage 20.8 billion wirelessly-connected “things” throughout the world by 2020. At present, it is estimated that 5.5 million new ones are connected every day [2]. This is a huge challenge for mass data storage, which currently relies on hard discs. Everything we download daily onto our computers or mobile phones is stored magnetically on millions of these spinning discs located in data centres scattered across the planet’.

‘One main contender for the future of mass storage is MRAM (Magnetoresistive random-access memory), under development since the 1990s. MRAM is faster and offers higher density compared to other non-volatile RAMs. A large amount of research has been carried out in developing it, but MRAM has not been widely adopted in the market yet, largely due to the costs and complexity of large scale fab manufacturing. Our team in AMBER, at Trinity College Dublin, may now have solved the problem, offering a simpler solution for manufacturing a type of MRAM.’

The team, who are made up of experts in magnetism and magnetic switching, which is at the heart of data storage, have managed to circumvent the need to use a magnetic field. Their elegant new device consists of a stack of five metal layers, each of them a few nanometers thick. At the bottom is a layer of platinum, and just above it is the iron-based magnetic storage layer just six atoms thick. Platinum is a favorite of researchers in spin electronics, the technology that makes use of the fact that each electron is a tiny magnet. Passing a current through the platinum separates the electrons into two groups with their magnetism pointing in opposite directions at the top and bottom surfaces thanks to an effect known as ‘spin-orbit torque’ that follows from Einstein’s theory of relativity. Electrons at the top are pumped into the storage layer and try to switch its magnetic direction, but like a pencil balanced on its point, the magnetism of the storage layer can’t decide which way to fall. The team designed the rest of the stack to solve that dilemma by acting like a nanoscale permanent magnet that creates the small field necessary to make the switching determinate, at zero cost in energy.

The Group now plans to demonstrate a full memory cell, and an ultra-fast oscillator based on spin-orbit torque using layers of a novel magnetic alloy they discovered recently. The device stacks will be grown in a sophisticated new SFI-funded thin film facility in the AMBER Centre at Trinity’s CRANN Institute for nanoscience. These new spintronic devices have potential to deliver the breakthrough needed to sustain the information revolution for another 25 years.

[1] The full paper is published online at the below link:
http://dx.doi.org/10.1038/nnano.2016.84

[2] http://www.gartner.com/newsroom/id/3165317

Researchers in AMBER, the Science Foundation Ireland funded materials science centre, hosted in Trinity College Dublin, have discovered a new behaviour of the wonder material graphene. Efficient ways to pattern and assemble graphene, especially in parallel, have remained a significant challenge for researchers worldwide. The research breakthrough published in the prestigious journal Nature this week introduces a significant new fabrication method for graphene, as well as creating new technologies that harness the properties of these molecular sheets in ways not previously envisaged.

The team – consisting of Professor Graham Cross and postdoctoral fellow Dr. James Annett of AMBER and School of Physics at Trinity College Dublin – found that they can induce graphene, a sheet of the element carbon only one atom thick, to spontaneously assemble into ribbons and other shapes while lying on a surface. The effect is potent enough to make large graphene structures almost visible to the naked eye, and it operates in air at room temperature.

In the short term, the AMBER researchers expect their findings will be useful to pattern graphene sheets to simplify the production of electronic and other devices in larger volumes. However, they also think the self-assembly effect itself may be important as an active component of future sensors, actuators and machines.

James Annett who was a graduate student in Cross’ lab at the time of the discovery, said: “I was investigating the properties of graphene as a kind of dry super-lubricant. One day I noticed that cut-out shapes that had been formed during my experiments were changing over time. When I looked more closely, I found that beautiful, well-defined structures had formed in the graphene sheets all by themselves. I realised then that the methods we were using to investigate friction were actually configuring the graphene to spontaneously rearrange itself.”

Fundamentally, the observations reported by the authors in the journal Nature reveal how heat energy causes a flat graphene sheet to try to form its more familiar three dimensional state known as graphite. A mathematical model to explain why the effect works is included as part of their publication. Cross believes this is a new class of solid matter behaviour specific to molecularly thin sheets.

Comments Professor Graham Cross, “Over twenty years ago, it was suggested that graphene could be deliberately folded and cut into useful shapes as a kind of molecular origami. Our discovery shows there exists a much richer potential for these kinds of two dimensional materials. We can make them behave like a self-animated sheet that folds, tears and slides while peeling itself away from a surface. Even better, we have figured
out how to control the effect and make to it happen in different places in the sheet at the same time.”

Graphene is part of a family of recently discovered two dimensional materials that may revolutionise the electronics used in smart phones and computers, as wells as produce light, high strength composite materials. Now,
with the phenomena of self-assembly added to their list of abilities, these materials might enable new devices known as nanoelectromechanical systems which are connecting up the virtual world to the real world through the Internet of Things.

Professor Michael Morris, Director AMBER, said: “This exciting discovery shows that Irish research is at the leading edge of material science worldwide. Our researchers are working to address the big issues facing modern society – across healthcare, energy, transport and other areas. This self-assembly of graphene discovery which was previously thought impossible opens up new possibilities for the development of future technologies. Key applications are for instance fast electronic and optical devices, flexible electronics and functional lightweight components.”

The paper can be found here: http://dx.doi.org/10.1038/nature18304

On June 28th 2016, AMBER, the Science Foundation Ireland funded materials science centre based at Trinity College Dublin, launched their EngAGE with Science Toolkit, an intergenerational programme which introduces the world of materials science to schoolchildren and senior citizens. During 2015, AMBER and its project partners, Trinity EngAGE, Trinity Access Programme, Age Action, St Andrew’s Resource Centre and Campus Engage, facilitated this project for twenty-two 6th Class students of St Brigid’s Primary School and seven adult participants of St Andrew’s Resource Centre.

Throughout this 8-week programme, participating children and adults were given insight into the kind of work which is done in a nanoscience research centre. They toured AMBER’s microscopy labs and viewed the powerful electron microscopes housed there. They also met many of AMBER’s researchers who gave a first-hand account of what it’s like to be at the cutting edge of Irish nanoscience research. The EngAGE with Science participants visited AMBER Centre, St Andrew’s Resource Centre and St Brigid’s Primary School as a way of sharing their new knowledge of materials science amongst every member of the programme. In the final week of EngAGE with Science, all involved were presented with certificates of participation and prizes were awarded to winning entries in a group poster project.

Miriam Harte, AMBER Education and Public Engagement Officer said, “EngAGE with Science offered a unique approach to intergenerational learning between primary students and senior citizens. The enthusiasm within the group was contagious and helped make the programme hugely enjoyable for all involved. Each week our community of participants looked forward to seeing one another and learning more about materials science research together at Trinity College Dublin. Here at AMBER, we were absolutely delighted to have been given this opportunity by Science Foundation Ireland throughout 2015.”

EngAGE with Science” was funded through the Science Foundation Ireland’s Discover programme in 2014. The project ran from May to December 2015. Any further queries about this programme should be directed to ambersfi13@gmail.com.

The development of a real alternative to fossil fuels is perhaps the greatest technological challenge faced by humanity at present. Now, researchers at AMBER, the materials science centre funded by Science Foundation Ireland and based at Trinity College Dublin have developed a material which enhances the splitting of water at a very low energy cost using earth abundant raw materials. This new material performs as well as the world’s most effective material for water splitting (which is the scarce and expensive ruthenium oxide) but is much less expensive. This is a significant breakthrough, as it means that an energy efficient production of pure hydrogen is now possible using renewable energy sources which will potentially accelerate adoption of hydrogen as a fuel in energy efficient transportation.

Hydrogen has been described as the ultimate clean energy source, it’s seen as very attractive as it is a pollution free fuel and energy carrier which would satisfy much of the energy requirements of our society. Hydrogen is readily prepared by splitting water electrically into its component parts hydrogen and oxygen (a process called electrolysis).

However, this process requires a significant energy input. The widespread uptake of hydrogen as a fuel has been hampered by the lack of low cost, earth abundant materials which can accomplish the splitting of water, with minimal energy input, in an economically efficient manner using renewable energy sources.

The AMBER breakthrough recently published in the prestigious international journal ACS Catalysis, has shown that the ruthenium content can be decreased by as much as 90% and substituted with the earth abundant and inexpensive manganese oxide without diminishing the efficiency of the material to split water.

Professor Mike Lyons, Investigator at AMBER and Trinity’s School of Chemistry: “We are very excited about this very significant breakthrough. The adoption of this material in industry will mean that electrochemical hydrogen generation using photo (electrolysis) is now far more economically viable and will hasten adoption of hydrogen as a fuel in energy efficient transportation. It should be noted that this discovery could only have been accomplished using the world class characterization facilities and opportunity for interdisciplinary collaboration available within the School of Chemistry and AMBER.”

Lorraine Byrne, Executive Director CRANN Institute and AMBER National Centre: “Our team of researchers at AMBER always strive to bring excellent science with potential environmental and societal impact. This scientific breakthrough brings us one step closer to a realistic energy alternative.”

Mike Lyons, continued: “Our disruptive materials breakthrough is momentous as it means much more energetically efficient and more economical hydrogen energy. This means that the cost of producing hydrogen via water electrolysis will be significantly reduced, which will result in a more rapid uptake of hydrogen as an automotive fuel.”

Professor Mike Lyons leads the Trinity Electrochemical Energy Conversion and Electrocatalysis Group. He has published two books and more than 126 papers, and has a h-index of 33, which demonstrates the worldwide impact of his research. Working with Professor Mike Lyons, was PhD student, Michelle Browne.

The full review is available at:http://pubs.acs.org/doi/full/10.1021/acscatal.5b02069