The August issue of ATAP News features the latest advancements in next-generation laser-plasma accelerators (LPAs) aimed at creating more compact particle accelerators and higher-field superconducting magnets made from new materials. These developments, driven by ATAP researchers, are vital to future high-energy and particle physics, quantum technologies, fusion, medicine, materials science, and many other fields.

Researchers from our BELLA Center, a leading facility that advances high-power lasers and their applications, have successfully demonstrated how intense light pulses from a free-electron laser (FEL) can be driven by an LPA. This work brings compact FELs closer to practical use in science and industry.

To further improve the performance of LPAs, our teams are developing new tools to monitor and address instabilities in high-power lasers used in LPAs. For example, a new diagnostic tool enables real-time tracking of spectral phase instabilities, which reduce LPA performance, without interrupting laser and accelerator operations. This is part of ongoing efforts, including recent work that employs machine learning-enabled predictive control to stabilize a high-power, low-repetition-rate laser, which provides a practical way to stabilize intense ultrafast laser pulses and to produce LPAs and FELs with precise, repeatable performance.

By combining two different numerical modeling techniques, our researchers have created a more accurate and cost-effective way to simulate dynamical processes in LPAs. Their approach could help improve the design of staged LPA systems and, potentially, future plasma-based linear colliders.

Our Superconducting Magnet Program (SMP) has also developed a new method for measuring inter-tape contact resistance in rare-earth barium copper oxide (REBCO) tapes used in high-temperature superconducting (HTS) cables. The research provides deeper insights into current sharing among these cables, improving our understanding of inter-tape contact resistance and paving the way for designing better HTS cables that produce more powerful and cost-effective superconducting magnets for use in accelerators, medicine, fusion, energy storage, and beyond.

Researchers from SMP are also investigating how these REBCO-based HTS cables will endure the extreme conditions found in magnetic confinement fusion reactors, which are among the leading technologies for achieving fusion energy. The research has identified several major limitations to the durability of REBCO tape in the intense radiation environments expected in the reactor, such as physical swelling and degradation of the critical current. This work could lead to improved manufacturing techniques for HTS magnets used in fusion applications.

Nurturing the next generation of science and technology professionals is essential to the Lab’s mission. To achieve this, throughout June and July, ATAP staff and colleagues from the Lab’s Workforce & Development Office led guided tours for our current summer intern groups at BELLA and the Lab’s Advanced Light Source.

And finally, congratulations to Jens Osterhoff, who has been appointed director of the BELLA Center. Jens is internationally recognized for his work on plasma accelerators and facilities. His appointment took effect on July 1, 2025. Jens succeeds Eric Esarey, who led BELLA since 2019 and will now serve as a senior science advisor to the center. Congratulations to Jens on his appointment, with thanks to Eric for his leadership and best wishes in his new role.

Written by Carl A. Williams or other authors as credited.

For more information on ATAP News articles, contact caw@lbl.gov.