The hunt for the perfect beam of light

The hunt for the perfect beam of light

Mikael Eriksson, former Machine Director and Design Coordinator at MAX IV Laboratory, has devoted his entire working life to making the invisible visible with the help of ultra-short wavelength light. An old mangle, aluminium foil, limited resources and a large portion of ingenuity have been important elements in the process of developing the world’s best materials research facility.

It could be said that the basis for today’s enormous accelerators was established in the late 1600s, when the Dutch scientist, Christiaan Huygens, presented his ground-breaking work on the wave theory of light. He asserted among other things that it is impossible to see something that is smaller than the wavelength of the light that illuminates it. Since then, science has relentlessly looked for ways to shed new light on the exciting microcosm, invisible to the naked eye, which surrounds, and affects, us all.

It was not totally unexpected that Mikael Eriksson would devote himself to the natural sciences at a high level. His uncle, the world famous physicist and Nobel Prize winner Hannes Alfvén influenced Mikael Eriksson’s boyhood interests to a great extent. It was Alfvén who persuaded him at the age of 12 to build his own transistor radio. Later he inherited some of his uncle’s discarded measurement instruments.  So, an interest in the natural sciences developed early, but he did not find all the subjects appealing.

“Oddly enough I was never interested in chemistry when I was at school”, says Mikael Eriksson. “In fact I got the worst grade – a C – in the subject at upper secondary school. Physics on the other hand had a hold on me from the start and it was a joy – pure and simple. The subject was like a chess game and the thing was to understand the interaction of the various natural laws and think many steps ahead. Physics triggered my curiosity and that decided my path. It is fun working in physics. It’s also the advice I give to young people who are uncertain about starting a professional career. Devote yourself to what interests you, then you will succeed.”

After upper secondary school, Mikael Eriksson studied mathematics and physics at Lund and gained his doctoral degree in 1975 with a thesis on the design of a new electron accelerator. This was primarily intended for experiments in nuclear physics, but could also produce synchrotron light, which opened up new possibilities for investigating molecular structures. The thesis was the starting point for what would become Sweden’s first synchrotron radiation facility, MAX I in Lund.

Carl XVI Gustaf at the inauguration of MAX-lab 1085.
Carl XVI Gustaf at the inauguration of MAX II 1995.

During this period there was considerable international interest in materials research using synchrotron light, but nobody in Sweden was prepared to pay for the country’s own facility. With a lack of sustainable financing, Mikael Eriksson and his colleagues did all they could to find short cuts, because they were determined to build a synchrotron radiation facility ­– anything else was unthinkable.

“We had very little money, but we knew our physics, saw the possibilities of synchrotron light and had a burning determination to achieve something fantastic. That made us inventive. We scoured the market for standard components, often second hand, that could replace the special components we couldn’t afford to buy, and we found totally new and unconventional ways to build and combine the various parts. The electromagnets, for example, were glued together using a mangle that we borrowed from a colleague’s mother. The magnets turned out well, but the mangle could never be used again.”

After several years of hard work and hunting for grants MAX I was completed in 1985, housed in its own building in the LTH area of Lund. Considering the enormous investments in the synchrotron radiation facilities being built around the same time in Japan and the USA, it is easy to dismiss the DIY approach that resulted in Sweden’s first facility. However, Mikael Eriksson considers that, in fact, it was this lack of resources that produced the leading-edge knowledge that many benefit from today.

“Our limited circumstances have quite simply forced us to be a little more ingenious than the others and to take calculated risks. Without this approach we would never have been able to develop MAX I or its successors – it would have been far too expensive.”

Mikael Eriksson and his research group did not allow themselves to rest on their laurels for long. Only a couple of years after the opening of MAX I, work began on the next major project and the new, larger accelerator ring, MAX II, was completed in 1995. Now, the laboratory could offer an even more brilliant beam of light. Researchers from all over the world streamed to Lund to use technology that produced high resolution images of previously invisible molecular structures.

Investigations using synchrotron light had been the basis for several Nobel Prizes around the year 2000. Synchrotron light had also become an established investigation method for industry, which wanted to develop materials with new properties. Thinner computer screens, more efficient dialysis machines, more accurate medication, improved lubricants, faster computers and more sustainable and eco-friendly car engines are just a few examples of what has become possible, due to the increasingly advanced possibilities to study materials opened up by synchrotron light technology. A profusion of new facilities with ever more brilliant and focused beams opened around this time in response to demand from research and industry, and driven by enormous government investments in the USA, Japan, China and South America. However, it all came to a halt just a few years later.

“It is clear that technological development in this field has been at roughly double the rate of that within the computer field, with beams that have become increasingly brilliant and focused, but it all suddenly stopped in 2002. Synchrotron light technology was considered to have reached its limit.”

The driving force in this rapid development had been to attain an electron beam that was as narrow, sharp and focused as possible. The problem was that a narrower beam became increasingly unstable and difficult to capture, and around the year 2000 a limit had been reached.  The research world talked about a “chromacity brick wall”, and the only way to break through the barrier was to build even larger accelerator rings at a cost that would be completely indefensible. However, researchers in Lund had other ideas.

“We started to look at new ways of arranging the magnets that lead the electron beam around the accelerator ring. Mathematical models showed that a larger number of magnets, arranged in a certain way, could eliminate the instability. When we presented our results to other researchers there were few who believed us. ‘You must be mad’ was a common reaction, but we believed in our calculations and continued working. The aim was to take the lead again, to build the world’s best accelerator ring, but there were many problems to solve along the way. The biggest was that an accelerator ring, even using our technology, would need to be several kilometres long and it would be totally impossible to finance. We needed to find a way to get through the brick wall with a smaller accelerator, and to make that work we needed to test new paths in the required environment.”

The solution was MAX III, a new accelerator completed in 2005 that acted as a prototype for MAX IV. It was here that Mikael Eriksson and his colleagues could fine-tune the new solutions that were necessary to fulfil the objective – to create the world’s most brilliant X-ray beam using limited resources. One problem was the large number of magnets required. To reduce their size it was necessary to give each magnet several different functions. Producing these magnets was complicated and required almost unimaginable precision, but it was shown that the technology worked. Using MAX III the researchers had broken through the impossible “brick wall” and the path was now open for the crowning glory, MAX IV, whose beam will have a brilliance 10,000 times greater than that of MAX III and ten times greater than anything previously seen.

Mikael Eriksson and Pedro Fernandes Tavares inspects one of the magnet blocks in the 3 GeV ring
Mikael Eriksson and Pedro Fernandes Tavares inspect one of the magnet blocks in the 3 GeV ring. Photo: Madeleine Schoug.

“Many of those who didn’t believe us at the start have now come round, and our multi- function magnets are now set to be used in a number of facilities around the world. They just want conclusive proof that MAX IV actually works first.”

The serious development work has attracted considerable attention and has led to Mikael Eriksson being awarded a number of prestigious prizes, including the Royal Institute of Technology’s major prize, the European Physical Society’s Rolf Wideröe Prize for ”outstanding work in the accelerator field” and, most recently, a gold medal from the Royal Swedish Academy of Engineering Sciences.

“Really, it’s unfair that just one person receives these prizes. The technology that broke through the ‘brick wall’ is all about teamwork. I see winning so many prizes primarily as a confirmation that the tool we have created is valuable for a number of different areas, both in research and industry.”

Mikael Eriksson describes himself as a competitive person and the small, highly qualified group of researchers that make up the international synchrotron light elite as extremely competitive.  However, a quick glance at his CV presents a slightly different picture. Mikael Eriksson is a member of almost every advisory committee to the world’s leading accelerator facilities. Is he there to monitor the competitors, or does he actually share the knowledge he has been involved in generating? According to Mikael Eriksson, the answer is both yes and no. It is a question of give and take.

“In this field you must want to come first, otherwise you will be helplessly left behind. But of course, the driving force in the research world is to be generous with your discoveries. It is by publishing and sharing new insights that we build our networks and careers, and gain access to greater resources. The accelerator world is no exception. The competition spurs us on to enhance our performance. The result is a refined technology that gives us an improved understanding of the world around us and that, ultimately, is what physics is all about.”

Mikael Eriksson has devoted 45 years of his life to accelerator physics. As a leading expert he could have found challenging and rewarding assignments almost anywhere in the world, but has chosen to stay in Sweden, which he feels offers unique conditions.

“It’s common abroad that large accelerator facilities are run as independent institutes. It has been a big advantage for us to be a part of a university with a number of different disciplines. These have been able to help us solve problems, and have also understood the benefits for their own research of having a world-class facility on the doorstep. Although this may sound strange, Sweden also has a significantly less complex bureaucracy than many other countries. Decision-making processes are straightforward and clear. You get a decision relatively quickly and you can trust promises that are made. This provides a calm atmosphere, allowing researchers to concentrate on what we do best – producing new knowledge and building fantastic research facilities.”

Mikael Eriksson also praises the corporate culture that has made it possible to find short cuts and implement new, smart solutions.

“Locally, there are highly advanced, small technology companies that we cooperate with. They have approached our ‘impossible’ tasks with great expertise and enthusiasm. Without them and the cost-effective solutions we have developed together, MAX IV would never have become a reality.”

MAX IV has been built for a fraction of what an accelerator would have cost using traditional technology. However, despite its relatively small set-up costs, the construction and operation will still require a major injection of taxpayers’ money. How is research going to repay this?

“This will require good teaching skills”, comments Mikael Eriksson. “It’s not only about getting results, but also making people understand what the results actually mean. A part of the research that will be conducted at MAX IV is pure curiosity-driven research, i.e. research whose usefulness is difficult to explain now, but which may be of great significance 20 or so years down the line. The research that laid the foundations of modern computer technology several decades ago is an example of such research, and there are many more. But then we also have a responsibility to get people to really understand the knowledge and also implement it in their everyday lives. Much of what is called materials research has a direct bearing on the major challenges the world is facing ­– climate, water provision, health and so on. If knowledge about how we can live in greater harmony with the world around us does not reach the general public in terms of lifestyle changes, it is not worth very much. Nevertheless, it should be remembered that a lot of the knowledge we have produced does actually benefit people eventually in the form of new, better, more energy-efficient, eco-friendlier technology that also contributes to economic development.”

MAX IV sedd från luften i juni 2015
MAX IV aerial photo June 2015. Photo: Perry Nordeng.

For Mikael Eriksson, MAX IV is the final chapter in a long and exciting working life. He is looking forward to leaving a life of detailed planning and having more time for his many leisure activities including favourite pastimes such as kayaking and long distance ice skating. However, he will not be leaving the scene altogether, as there are far too many exciting projects around the world to get involved in and the prospect of a totally perfect beam of light still shimmers like a mirage in the distance. One of the results of more than 40 years of work on developing and operating world-class synchrotron radiation facilities is that the sharpest and most inventive minds in accelerator physics have sought their way to Lund from every corner of the world.

Eshraq Al Dmour, Chiara Pasquino och Martin Johansson har varit med och byggt MAX IV.
Eshraq Al Dmour, Chiara Pasquino and Martin Johansson are part of the installation team at MAX IV. Photo: Johan Persson.

“Some talented people will be taking over,” says Mikael Eriksson with a smile.

So what was the story with the aluminium foil?

BioMAX - mycket folie blir det
BioMAX – and a lot of foil. Photo: Johan Bävman.

“Well, it emerged early on that ordinary aluminium foil works very well for increasing and maintaining heat in the beamlines, where the experiments take place. This unconventional solution is perhaps not that beautiful, but it has something important to offer even in a facility that costs billions of Swedish crowns.”

 

Story by: Arne Berge

Photo featured image of Mikael Eriksson: Madeleine Schoug