90 Years of Excellence in Accelerators

How do the Lab’s accelerators support the Lab’s mission?
The Laboratory’s leadership in these areas is based on the twin central legacies of E.O. Lawrence. One is the accelerators themselves; he of course invented the cyclotrons that started modern accelerator science. His other legacy—comparable to particle accelerators in its revolutionary nature and breadth of influence—is team science, which is foundational to our own workstyle and our numerous intramural and extramural partnerships, and is fundamentally necessary for the scale of much of the research we perform today. We invite you to watch the Berkeley Lab video Excellence in Accelerators to learn more about what we do, why, and how.

Particle accelerators and accelerator-based photon sources are indispensable engines of scientific discovery and are used in applications across industry, national security, and medicine. Here at Berkeley Lab, the Advanced Light Source (ALS) is a shining example. It accelerates electrons and uses precise control of electron beams to create soft x-rays to probe matter. Thousands of users a year explore materials, improve batteries, advance biosciences, and more with these x-ray beams. We are also extensively involved in designing the next-generation version of this user facility, the ALS Upgrade.

Extending the capabilities and reducing the size and cost of accelerators hold the key to several grand challenges of science, including better understanding the structure of the universe through high energy particle physics; creating brilliant photon sources for basic energy sciences and materials; and exploring new states of matter. These and related systems are also crucial to fusion energy sciences. ATAP is driving the extension of existing particle accelerators using advanced magnets, controls, simulations, and beam physics. For example, new high-field magnets are being used to upgrade the Large Hadron Collider in its search for new particles, as well as in compact fusion-energy concepts.

At the same time, we are creating new compact accelerator technologies and the lasers that drive them, with the potential to greatly extend the reach of fundamental science and also to make the advanced capabilities developed in leading-edge large scientific facilities such as the Advanced Light Source available to applications from medicine to security. For example, advanced laser-driven accelerators may form the basis for the next generation of very high-energy colliders. In addition, making high-performance accelerators compact enough to fit in a clinic or factory could support improved cancer detection and treatment, precision nondestructive measurements required for advanced manufacturing and nuclear security, and environmental carbon sensing for understanding global climate.

What are the top 3 or 4 areas of interest or areas of growth for the accelerators today?
The top drivers for the next generation of accelerators include: enabling new advances in fundamental physics; advancing medical and security measurements and treatments; creating clean fusion energy; and enabling tools for a carbon economy and quantum information science. Developing the required performance requires drawing on a wide variety of technologies and areas of scientific research. The Laboratory is uniquely positioned to do this through our interlinked programs in superconducting magnets and advanced precision controls that are the key to next-generation accelerators and fusion devices, laser-driven particle accelerators that offer transformative compactness and the lasers that drive them, accelerator physics for light sources (including ALS and ALS-U) and particle colliders, and accelerator and fusion applications. Computing is a vital tool throughout, and we both use and advance the state of the art in high-performance simulations and tools leading the push toward the exascale, and apply artificial intelligence and machine learning feedback concepts that enable understanding and control of the complexity required for high performance. Key directions include:

•  Extending the capabilities of accelerators for high energy particle physics at the energy and intensity frontiers, as well as next-generation photon sources. New high strength magnets are extending the reach of discovery at machines like the Large Hadron Collider that probe fundamental particle physics and expand our understanding of the basic physical laws that are at the root of the physical sciences. Feedback controls (including AI/ML) and advanced simulations allow us to better understand and control complex systems, extending performance both for photon sources like ALS-U and for colliders.

•  Pioneering a new generation of radically more compact accelerators, which achieve in centimeters what takes current technologies hundreds of meters. Using intense lasers to drive waves in ionized plasma, we circumvent the limits on how much acceleration present-day machines, based on radiofrequency power in resonant metallic cavities, can impart to particles. This has the potential to enable much higher energy systems at a physically and financially practical size, extending the reach of basic science in understanding fundamental physical laws and the structure of the universe through high-energy particle physics. These fundamental interactions are at the heart of physics and the physical sciences. En route to this long-term goal of a collider, this line of research could enable a new generation of laboratory-scale free-electron lasers and other photon sources.

•  Creating capabilities to bring the power of Berkeley Lab science to the world. To take a few examples: A compact neutron source and detector system could enable sensing of the amount and distribution of carbon in the soil, a key to moving toward a low-carbon economy to protect the global climate. Compact charged particle sources are being used to research new methods of radiotherapy for cancer treatment. Compact accelerators creating precision photon sources allow X-ray images to be taken with much greater resolution and reduced radiation dose, improving medical screening and security applications. High field magnets would make a potential fusion energy source more compact and affordable. And high-intensity beams create new states of matter, including unique ways to form qubits for quantum information science.

•  Building a new generation of lasers that combine high average power and high peak power in short pulses. Nearly-continuous lasers have already transformed many industrial processes, such as welding, by delivering kilowatts of average power with precision. Short-pulse lasers, lasting less than a trillionth of a second but with peak powers of hundreds of trillions of watts, unlock new physics interactions, including the keys to new laser-driven accelerators, tailoring material surfaces to create hydrophobicity or other properties, and more. We are pioneering the coherent combination of many ultrafast fiber lasers to create the short pulses at high repetition rates and average powers that are required for these and other applications.

These endeavors are made possible by our people. ATAP emphasizes mentorship to develop the national scientific workforce and educate the next generation – from students and postdoctoral researchers to career staff. ATAP’s strong divisional operations team is key to our success with complex projects, multi-agency engagement, and collaboration across the Laboratory. We place great emphasis on the Lab’s IDEA goals, including an active IDEA committee and participation in employee resource groups (I am an active member of the Lambda Employee Resource Group). We want ATAP to be a place where everyone feels that they are valued and that they can reach their full potential—a place where we don’t just accept differences, but celebrate them, which improves both the work environment and the results.

Who do you partner with at the Lab to be successful?
Because accelerators are essential tools across the sciences and for society, we partner broadly across the Laboratory. To give just a few examples, we are conducting experiments with the BioSciences Area on how the short pulses of ions produced by new plasma accelerators could improve cancer therapy. Together with the Nuclear Science Division, we are developing and testing sources of mono-energetic X-rays that could revolutionize sensitivity and reduce the radiation dose required for imaging needs across medicine, security, and industry. We partner with the Physics Division on combinations of accelerators and detectors that will advance our understanding of the structure of the universe through high energy particle physics. We create computer simulation codes and methods to understand and control complex systems in coordination with Computing Sciences and NERSC. We support Advanced Light Source operations and the Advanced Light Source Upgrade project with beam physics, diagnostics, and controls that push the facility beyond the state of the art; the result benefits soft-x-ray users throughout the physical and life sciences.

Developing new accelerators and new experiments means new configurations and capabilities, so we collaborate with the Environment, Health and Safety Division to bring those on line safely, even including testing of radiation detectors in new regimes of very short pulses. ATAP’s activities are based on a vital partnership with the Engineering Division, which provides advanced design work, dedicated mechanical and electrical shops working hand in hand with experiments, and specialized expertise and collaboration supporting our ability to execute major projects. The Laboratory’s and ATAP’s excellent support staff — including administrative services, finance management, facilities, human resources, communications and lab operations functions — are also essential to our ability to do these things. As Newton put it, we stand on the shoulders of giants. We are grateful to the many people who help us make the climb.

Antoine Wojdyla grew up in the Caribbean, on the French islands of Guadeloupe and Saint-Martin. He had no scientists in his family as role models, but his interest in the wonders of science were set in motion from his grandfather who was a woodworker. His grandfather built him a toy cart and he added a bulb, battery, and wires. Antoine was amazed at what happened when touching the wires turned the light on and deemed his grandfather a magician. He was informed that it was not magic, but science, that could be learned. He was encouraged to be curious not only by family members, but from teachers and professors.

He moved to mainland France and received his Ph.D. from Ecole Polytechnique, a school near Paris, where he studied terahertz radiation, a kind of electromagnetic wave that sits between infrared and microwaves.

He was interested in terahertz radiation since it can see through materials while producing acceptable resolutions for imaging. This technology is used in body scanners in airports and 5G telecommunications. While this work is not related to his current work at the Lab, his early experience and ideas are transferable to his current work.

One of Antoine’s favorite quotes comes from his colleague and mentor Ken Goldberg. “There are only two kinds of people who really enjoy doing their jobs, baseball players and physicists.” Antoine says he doesn’t know much about baseball, but physics sure is a great occupation.

When did you come to the Lab?
I came to the lab about nine years ago, where I started as a postdoc at the Center for X-Ray Optics, studying extreme ultraviolet (EUV) lithography, which is the latest technology in semiconductor manufacturing. iPhone 12 chips are made using this technology, and the Lab and the ALS have been at the forefront of research in this area. For a while I thought I would bring my scientific expertise to industry, but I realized that the environment at Berkeley Lab was quite unique and would allow me to conduct research better than anywhere else. Plus, we undoubtedly have the best view from our offices, and a community which truly believes in improving the fabric of academia.

Around the same time in 2016, the Advanced Light Source was starting the conceptual design for an upgrade, and I was asked if I wanted to join. It wasn’t a very hard decision to make.

What are you currently working on?
I am currently working on the upgrade of the Advanced Light Source (ALS-U), which is a large-scale DOE project. The goal is to turn the facility from a very fancy flashlight to a laser-like source of x-rays, the so-called “4th generation” of synchrotrons (diffraction-limited storage rings) where we eventually reach the limits of what is permitted by physics.

The project is roughly divided between the accelerator systems and the beamline and optical systems, which I’m part of. My role is to design the new beamlines that will operate on day one after the upgrade, taking advantage of the unique properties of the source. We work with beamline scientist to understand what they want to be able to conduct experiments with what will be the most coherent synchrotron radiation in the world, and together with engineers we define tolerances to provide them what they need based on the state of the art of mechanical and optical engineering: everything has to be very precise – aberration measured in pico-feet and not allowed to move by more than a nano-inch.)

It’s also great to work with colleagues from the accelerator side, learn how they handle electrons and see how we can adapt these techniques to measure our bright photons. We develop new enabling technologies such as x-ray wavefront sensing and adaptive optics, and sometimes borrow ideas, such as using machine learning to compensate for minute deformations caused by every residual drift and non-linearities.

I’m also learning a lot from colleagues from other U.S. light source facilities: there is a great spirit of collaboration at the national level.

What big challenge(s) are you hoping to solve with your work in the next 20 years?
Lately, I’ve been very excited by newly found links between superconductors and knots in the magnetic field called skyrmions and other strange topological effects. Soft x-ray light sources are ideal to look at these topics, and if we can understand how this all works, maybe we could manufacture superconductors working at room temperature.

If we can harness superconductivity, not only could you move energy from sunny to darker places, but you could also have flying cars. The internet brought a nearly frictionless flow of information and changed the world. Imagine what would happen if it was the same for green energy.

I think with laser-like properties of the upgraded ALS, there are many challenges we could tackle beyond better resolution and faster experiments. Things like adaptive optics, which means you literally change the surface of mirrors by a few atoms, could be possible. You could potentially use the light as a tweezer, create phase vortices to twist crystal lattices or, or 3D-print at the nanoscale.

Who from the past, present, or future would you like to collaborate with? And on what?

I want to collaborate with scientists from today! There is such an amazing pool of young scientists, and their make up is more diverse now than ever before. If we can harness the expected boost in science funding, we could change the face of academia. The current global health situation has been difficult for many, but particularly so for young scientists, and I sincerely hope we can make up for the crucial interactions that didn’t happen over the last 20 months.

Events such as the Lab Slam or area-wide seminars are ideal to start such conversation, and I think dissemination of knowledge through communication is very good overall. Thanks to that, I feel that there’s a great soil for collaboration among scientists from various fields, and many times I went on hike with colleagues working in biology or chemistry telling me about their research, and the next month see this kind of research featured in leading journals – understanding why it was relevant, but more importantly how I could help. With the end of Moore’s law, we have also become able to manipulate matter in exquisite ways, and I am very interested in learning more about the latest trends in material sciences.

On a different note, the current climate of information around global warming or public health measures worries me, and it’s inspiring to see scientists from the Lab taking a public role disseminating science ideas. That’s somewhere we can all learn from our colleagues.