This is part of a continuing profile series on the directors of the Department of Energy (DOE) Office of Science user facilities. These scientists lead institutions that provide researchers with the most advanced tools of modern science including accelerators, colliders, supercomputers, light sources and neutron sources, as well as facilities for studying the nano world, genomics, the environment, and the atmosphere.
Meet the director:
Most undergraduate students don’t get to visit one of the most powerful laser systems in the world. Most of them don’t grow up to run one of the most powerful laser systems in the world either.
Mike Dunne isn’t like most people.
In his third year at Imperial College, London, Dunne’s astrophysics class visited the British government’s nearby national laboratory. There, scientists used equipment that could focus more than 1000 times the power of the American electrical grid into a thin laser beam. The facility used these lasers to create extremely hot, dense matter that’s similar to some of the most extreme conditions in the universe. Dunne was hooked.
“I never looked back,” he said.
These days, he’s the director of the Linac Coherent Light Source (LCLS), a Department of Energy (DOE) Office of Science user facility at DOE’s SLAC National Accelerator Laboratory. The LCLS is a first-of-its-kind powerful laser that produces hard X-rays. Scientists use these X-rays to gain insight into biological, chemical, and material processes and structures.
As Dunne himself noted, “It’s been a nice circle of career development, from a wide-eyed undergraduate to somebody who helps shape the future direction of their field.”
The Director’s Background:
Inspired by his undergraduate experience, Dunne went on to receive his PhD in plasma physics from Imperial College. Next stop was the Atomic Weapons Establishment (AWE) Aldermastron, the U.K. government’s counterpart to laboratories run by the DOE’s National Nuclear Security Administration. Part of AWE’s research involved understanding plasma, gas made up of ions and electrons that aren’t bound together. Although Dunne started by conducting experiments, he eventually moved into theory, simulating how plasma inside stars works. He then went on to run AWE’s plasma physics program.
A decade after he started at AWE, the U.K. Central Laser Facility came calling. The facility he visited as a student now wanted him to take charge of their science program as director.
“It was too attractive,” he said. “Going to run this laser facility gave me the chance to peer into chemistry and biology and materials science. That was really exciting from a scientific growth point of view.”
While he was at the Central Laser Facility, his management helped the facility progress through a number of major upgrades and participate in coordinating programs across Europe. His success rate soon sparked the interest of other laboratories. The director of the National Ignition Facility — a device that uses the largest laser in the world to study fusion — at DOE’s Lawrence Livermore National Laboratory (LLNL) invited Dunne to the lab. From 2010 to 2014, Dunne ran the National Ignition Facility’s energy program.
When the position to run the LCLS opened up, it was an obvious fit.
“It blew me away in so many different ways,” he said. “Using this new tool was so far beyond anything that anyone had imagined before.”
The Facility:
The LCLS is the world’s first hard X-ray free electron laser. It produces 120 X-ray pulses a second, with each pulse lasting from 20 to 250 femtoseconds (one millionth of a billionth of a second). A femtosecond is to a second like a minute is to the age of the Earth. When it launched, the X-rays from the LCLS were a billion times brighter than any machine before it.
“The LCLS is truly an amazing beast,” Dunne said.
These X-rays allow scientists to take images more quickly than ever before. These images can track how atoms and subatomic particles, including electrons, move during chemical reactions. Like a high-tech flipbook, scientists can make these images into “molecular movies” that show these reactions in real-time. Most X-rays used for scientific research simply aren’t short enough in duration to create stop-motion movies that can freeze-frame the dynamics of an atom or molecule.
The speed also allows the LCLS to take extremely detailed, accurate images. Most high-powered X-rays that can provide that level of detail also damage the sample. The LCLS’s short pulses allow scientists to capture the image before the samples are damaged.
“The X-ray laser has allowed us to look at biological processes under real life conditions that have never been possible until now,” said Junko Yano, a senior scientist at DOE’s Lawrence Berkeley National Laboratory who uses the LCLS to study photosynthesis. “It’s essential to understand how plants use sunlight to split water that produces all the oxygen that our life depends on. But it’s also important for producing non-polluting renewable energy sources for our society’s needs, using just sunlight and water.”
The LCLS’s process starts with a laser that produces ultraviolet light. That light hits a copper plate, which releases electrons that are then accelerated to almost the speed of light. Those electrons are directed into a long, straight hall containing thousands of powerful magnets. These magnets wiggle the electrons back and forth, causing them to give off X-rays in response. The X-ray waves eventually line up, increasing their power and creating a thin, laser-like beam.
The LCLS produces both “hard” (the higher energy) and “soft” (lower energy) X-rays. Scientists use these X-rays for a variety of experiments, including understanding how X-rays affect matter, taking images of fundamental biological processes, and recreating conditions inside gas planets. Researchers using the LCLS have been able to investigate the structure of a toxin for killing mosquitoes, break down the steps of important chemical reactions, and better understand the intricacies of a wide range of fundamental problems in material science.
“The LCLS was a big leap into the unknown, and it was not at all clear whether or not it would even work. But the DOE took the gamble and just over 10 years ago, it paid off,” said Dunne. “We’ve been on this incredible journey of how best to make use of this really remarkable source of light.”
Ordinary Day:
Creating and carrying out the facility’s strategy requires a steady hand and mind. Meeting with scientists and running workshops helps Dunne understand the community’s needs and the future of cutting-edge science. That framework informs which researchers receive time to use the beam. The facility receives five applications for every spot available.
“The quality of the proposals that come in from the community is by and large outstanding,” Dunne said. “So unfortunately, some days it seems that my job is disappointing four out of five people I meet.”
Once the proposals are chosen, Dunne works hard to align and encourage his team to ensure optimal results. Keeping the facility in peak condition requires supporting the community of both technical staff and scientists. He said it’s important for him to be “providing that context and motivation and direction that can sustain people day to day as we go from month to month and year to year.”
One of the most rewarding aspects of his job is to touch base with the scientists during the experiments.
“Mike always stops by during our beam time and asks how things are going,” said Yano. “I think that’s great. It is a real morale boost to the entire hardworking and bone-tired group that the director of the facility took the time to come by to see how we are doing.”
Dunne said that seeing the scientists work, especially sharing in their sense of discovery, is one of his favorite parts of the job.
“Often, you’ll find there’s a point in that experiment where it just clicks. The data leaps out at you,” he said. “The sheer elation and joy … being around that and seeing it is really just the most spectacular feeling.”
To enable future discoveries, Dunne is leading the effort to make the facility as cutting-edge as possible. Coming soon, the LCLS-II (the upgraded LCLS) will produce X-rays with 10,000 times greater average brightness than the LCLS and deliver up to 1 million X-ray pulses every second. These increases will allow scientists to get more detail than ever before on chemical and biological processes. If the LCLS is like a flipbook, the LCLS-II will be like live-streaming high-resolution video. The increased capacity will also allow the facility to accommodate more experiments.
“My job is to make sure that we’re not just scientifically healthy today, but we’re scientifically healthy 10 years from now and beyond,” Dunne said. “A facility that pushes the state of the art in every direction.”
Typical Experiment:
When you have a camera like the LCLS, it’s possible to take images of almost anything. One of the major research areas is photosynthesis, a process that we know surprisingly little about, considering its importance.
Scientists are using the LCLS to understand how photosynthetic systems use sunlight to split water. Researchers using X-rays to study photosynthesis usually have to freeze their samples to limit the amount of damage. But the LCLS’s pulses are so fast that scientists take their images before damage occurs. The LCLS also allows scientists to watch the process in real time, so they can see far more steps than ever before.
“Looking at the sequence of events gives us much more information than looking at one picture,” said Yano. “It is a new way of looking at chemistry that was not possible before. Instead of one still picture, we now have many snapshots as it happens.”
Advice to a Future Director:
“Trust in yourself. You’re there because you have a scientific vision and an understanding of the field and the technology and the systems,” said Dunne. “Pull together a team that you can make sure gives you robust input and advice about what the art of the possible could be technologically. Gather a community so you understand scientifically what the most exciting and ambitious opportunities are out there. And then chart a course for the future.”
In 2018, the Linac Coherent Light Source and the other DOE Office of Science user facilities welcomed more than 36,000 researchers — from academic, industry, and government laboratories in all 50 states and the District of Columbia — to perform new scientific research. Learn more about the DOE Office of Science’s user facilities.
Please go to Profiles of User Facilities Directors to read more articles on the directors for the Office of Science user facilities.
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