Berkeley Lab



A message from Associate Laboratory Director James Symons

Part of two-page spread from Nobel Prize background document, showing cover and BELLA discussion
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Dear colleagues,

This year’s Nobel Prize in Physics was shared by three pioneers in the science, technology, and applications of lasers. Two of the laureates — Gérard Mourou and his then doctoral student Donna Strickland — won for a breakthrough that (among its many other benefits) made our Berkeley Lab Laser Accelerator Center possible.

Their Nobel-winning research brought “chirped pulse amplification,” a method of generating high-intensity, ultra-short pulses, to lasers. In a mere three pages, their 1985 paper “Compression of Amplified Chirped Optical Pulses” (Optics Communications 56, 3 (1 December 1985), pp. 219-221) sparked a revolution. The concept was implemented widely and almost immediately, ending a decade-long plateau in laser performance.

Today, CPA and follow-on developments are used near-universally at the peak-power frontier of very large research lasers, and also to increase the peak power of relatively small lasers for a wide variety of industrial and medical applications as well as research. (To take just one of many examples, some of you may be reading this with vision corrected by LASIK surgery, a technology made feasible for widespread use by CPA.)

We were immensely gratified to see laser-plasma acceleration, and specifically the multi-GeV electron beams obtained at the BELLA facility, mentioned as one of the examples of the benefits of CPA in the Nobel committee’s scientific background document. The BELLA Petawatt system is a 1 Hz repetition rate Ti:sapphire laser based on the CPA technique pioneered by Strickland and Mourou. In addition to the discussion, the Nobel backgrounder used a conceptual diagram of the LPA principle from the 2010 White Paper of the ICFA/ICUIL Joint Task Force on High Power Laser Technology for Accelerators —a figure that had originally appeared in an article by Wim Leemans and Eric Esarey in the March 2009 issue of Physics Today.

The white paper was produced by a joint task force, chaired by ATAP Division Director Wim Leemans, of the International Committee on Future Accelerators and International Committee on Ultra-high Intensity Lasers, and was based on a workshop series held first at GSI and then here at LBNL. The notional BELLA follow-on, which we call k-BELLA for its kilohertz repetition rate / kilowatt average power performance class, is an example of such a next-generation laser.

CPA is also one of the techniques used in an exciting collaborative project being conducted through our Berkeley Accelerator Controls and Instrumentation (BACI) Center: development of a laser system that uses “coherent combining” to achieve both high peak power and high average power from arrays of fiber-optic lasers.

Please join me in offering congratulations on the scientific stature and the widespread, ongoing societal impact of the research by Drs. Mourou and Strickland, as well as their co-laureate Dr. Arthur Ashkin. (He is a pioneer of laser trapping and the inventor of “optical tweezers” that use lasers to grasp tiny physical particles such as bacteria or viruses. His work had already figured into the 1997 Nobel Prize in Physics for our former Lab director and Secretary of Energy Steven Chu, who had worked with Ashkin at Bell Labs.) Their achievements have given us both game-changing tools and inspiration. This is a time for all of us to be proud of the important role we play as research pioneers and the resulting benefit to humankind.

James Symons
Associate Lab Director
Physical Sciences Area

BELLA’s Eric Esarey honored with Advanced Accelerator Concepts Prize

Eric Esarey, a senior scientist in Berkeley Lab’s Accelerator Technology and Applied Physics Division (ATAP), has been awarded the 2018 Advanced Accelerator Concepts Prize “for his pioneering theoretical research in the physics of laser-plasma accelerators.”

The prize, which recognizes outstanding contributions to the science and technology of advanced accelerator concepts, is awarded at the biennial Advanced Accelerator Concepts Workshop. Esarey joins a who’s who of researchers in cutting-edge approaches to particle acceleration, including ATAP Director Wim Leemans, who was honored in 2012.

Esarey came to Berkeley Lab 20 years ago, bringing plasma-theory expertise to the burgeoning effort in laser-plasma accelerators that is now known as BELLA Center. Previously he had worked for 12 years at the Naval Research Laboratory after earning his doctorate from MIT.

Theory and experiment have been partners in BELLA from the outset in the understanding of how intense lasers and plasmas interact, how an electron beam can “surf” the resulting electromagnetic wave, and how the promise of practical accelerators based on this principle might be fulfilled. Esarey serves as BELLA Center’s deputy, leading the theoretical and computational work that guides and supports the experimental efforts, and is also senior scientific advisor of ATAP Division.

Esarey was elected a Fellow of the American Physical Society (APS) in 1996 for “seminal scientific contributions to the physics of intense laser-plasma interaction.” In 2010, the APS honored him with the John Dawson Award for Excellence in Plasma Physics Research “for experiments and theory leading to the demonstration of high-quality electron beams from laser-plasma accelerators.”

AAC 2018 student-poster honors for BELLA’s Liona Fan-Chiang

BELLA Center and UC-Berkeley graduate student Liona Fan-Chiang was one of eight student poster honorees at the Advanced Accelerator Concepts Workship, winning for “Planar Laser-Induced Fluorescence for Custom Laser Plasma Accelerator Targets.”

Liona Fan-Chiang
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Liona Fan-Chiang previewed her award-winning presentation when DOE’s General Accelerator R&D Program Comparative Review came to LBNL in August 2018. Leemans and staff scientist Hann-Shin Mao collaborated with her on the work described in the poster.

The win continues an emerging tradition: Kelly Swanson of BELLA and UCB, who like Fan-Chiang is one of Leemans’s students, won student-poster honors at AAC 2016, as did Manuel Kirchen, a BELLA visitor from the University of Hamburg and DESY.

Berkeley Lab’s fruitful association with AAC continues

Fan-Chiang’s presentation was part of a strong Berkeley Lab presence (28 participants, who among them gave 20 orals, including three invited plenaries; three working-group summaries; and six posters) at the Workshop.

In 2020, the AAC Workshop will be hosted by Berkeley Lab (which had co-organized the 2008 AAC, together with UC-Berkeley). Esarey will chair the 2020 event.

Click to download Report of Workshop on Laser Technology for k-BELLA and Beyond (September 2017).

The topic of the workshop, held at LBNL May 9-11, was near- and long-term technology prospects for ultrafast lasers that could operate in the multi-kW to even tens-of-kW average power range. Such laser performance is needed for k-BELLA, further stepping stones to a laser-plasma accelerator relevant to high-energy physics, and spinoff benefits en route.

Leemans Wins IEEE’s Particle Accelerator Science & Technology Award

Brookhaven’s Ilan Ben-Zvi (l.) presents the award to Leemans
Dr. Wim Leemans, BELLA Center and Accelerator Technology and Applied Physics Division Director, was recognized with the IEEE Particle Accelerator Science and Technology Award. He received the award in an October 13, 2016 ceremony at the North American Particle Accelerator Conference (NA-PAC 2016).

Leemans was honored “for pioneering development of laser-plasma accelerators.” One of the leaders in the field, he is director of ATAP’s Berkeley Lab Laser Accelerator (BELLA) Center as well as of ATAP. He had already been elected a Fellow of the IEEE.

At each NA-PAC, the IEEE Nuclear and Plasma Sciences Society gives this award to two individuals who have made outstanding contributions to the development of particle accelerator science and technology.

“It’s quite an honor to be in such company,” says Leemans of the accelerator science and technology luminaries who have been recognized with the PAST Award. He joins four previous recipients from ATAP and its predecessor organizations, starting with inaugural winner L. Jackson Laslett and including Ronald M. Scanlan, Ka-Ngo Leung, and Alpert Garren.

BELLA Center’s Cameron Geddes Named a Fellow of the American Physical Society

CGRGeddes_150x180y_28July2015 BELLA Center’s Dr. Cameron Geddes has joined the ranks of Fellows of the APS. Geddes was honored in 2016 “for research demonstrating the production of high quality electron beams from laser plasma accelerators.”

APS Fellows are recognized by their peers “for exceptional contributions to the physics enterprise; e.g., outstanding physics research, important applications of physics, leadership in or service to physics, or significant contributions to physics education.” Geddes joins 25 other present and former staff members of ATAP and its predecessor organization, the Accelerator and Fusion Research Division, to be so honored. Six other researchers associated with Berkeley Lab also received the distinction in 2016.

Early Career Research Program Award for BELLA Center’s Jeroen van Tilborg

JVanTilborg_75x90y BELLA scientist Jeroen van Tilborg has received a DOE Early Career Research Program Award. He joins Chad Mitchell of the ATAP Division’s Center for Beam Physics among LBNL’s five 2016 recipients. They were among 49 winners nationwide out of 720 applicants in this prestigious Office of Science program for researchers who have received their PhD within the last 10 years. Click here for an LBNL Public Affairs story about the May 3 announcement.

BELLA Center Demonstrates Staging; Major Proof of Concept On Road to Future Laser-Plasma Accelerators

Staging_sim_cookie_150x149y Many laser-plasma accelerator (LPA) applications will require far more beam energy than is reasonable to achieve in a single accelerating stage. BELLA Center researchers have recently demonstrated coupling of an accelerated beam from one LPA stage into another. This is considered an essential technique for the future of LPA Their work is described in an article published February 1, 2016 in Nature.

In addition to being a pathway to higher energies, staging can also be used to decelerate an electron beam that has served its purpose, rather than sending it to a beam dump that must be shielded against the radiation that would result. This could further improve the compactness of, say, future light sources, or portable applications in homeland security or medical treatment.

To learn more, see the February 2016 edition of the ATAP Newsletter.

LPA_FEL_100x67y   Moore Foundation Backs BELLA FEL with $2.4M Grant

BELLA researchers will receive $2.4 million from the Gordon and Betty Moore Foundation to develop compact free-electron lasers that will serve as powerful, affordable x-ray sources for scientific discovery. This new technology could lead to portable and high-contrast imaging with x-ray accelerators to observe chemical reactions, visualize the flow of electrons, or watch biological processes unfold. To learn more, see the February 2016 edition of the ATAP Newsletter.

Workshops forge aspects of plasma accelerator futures

A pair of workshops hosted by ATAP Division in January, with results that are feeding into higher-level strategic-planning processes in the plasma-based-accelerator and laser-technology communities, will have implications for the next moves of BELLA and the future of accelerators. The Plasma-Based Accelerator Concepts for Colliders Workshop was intended to “identify the key physics and technology R&D needed to realize a plasma-based collider, and to formulate a nationally and internationally coordinated roadmap for carrying out this research over the next two decades.”

Besides electrons, the present and future BELLA lasers and laser-plasma acceleration concepts also offer the prospect of compact, efficient acceleration of ions. The repetition rate, spot size, and intensity of BELLA lasers could open new doors for discovery science related to plasma physics, high-energy-density physics, and nuclear physics, with spinoff prospects including cancer treatment and nuclear security. The Workshop on High Energy Density Physics with BELLA-i discussed this unique opportunity for discovery science as well as applications.

Visit the April 2016 ATAP Newsletter for more information on these workshops.

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