High-power laser pulses focused to small spots to reach incredible intensities enable a variety of applications, ranging from scientific research to industry and medicine. At the Berkeley Lab Laser Accelerator (BELLA) Center, for instance, intensity is key to building particle accelerators thousands of times shorter than conventional ones that reach the same energy. However, laser-plasma accelerators (LPAs) require sustained intensity over many centimeters, not just a spot focus that rapidly expands because of diffraction.

To achieve sustained intensity, the BELLA Center, at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab), uses thin hollow structures, or “capillaries,” containing a plasma to transport the pulses of light. BELLA Center scientists have been pushing toward longer and longer capillaries as they strive for higher beam energies with their LPAs.

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