High-power beyond extreme ultraviolet FEL radiation with flexible polarization at SHINE

TL;DR

This paper demonstrates that the SHINE facility can produce high-power, controllable polarization BEUV radiation at kilowatt levels, suitable for advanced lithography, by utilizing undulator tapering techniques.

Contribution

The study shows how SHINE's design enables generation of high-power BEUV radiation with controllable polarization, advancing FEL technology for industrial applications.

Findings

Kilowatt-level BEUV radiation achievable at SHINE.

Undulator tapering enhances energy extraction efficiency.

SHINE provides a pathway for high-power lithography applications.

Abstract

Linac-based free-electron lasers (FELs) feature high brightness, narrow bandwidth, controllable polarization, and wide wavelength tunability. With the rapid development of superconducting radio-frequency technology, linacs can now operate at MHz-level repetition rates, enabling FELs with both high repetition rates and high average power. Beyond extreme ultraviolet (BEUV) radiation is of great interest for scientific research and industrial applications, especially for next-generation lithography. Owing to the main design parameters of SHINE, the generation of BEUV radiation is a natural capability of the facility. The BEUV characteristics at SHINE are investigated and its achievable performance as a high-average-power light source is evaluated. By applying undulator tapering to enhance the energy extraction efficiency, kilowatt-level BEUV radiation with controllable polarization is shown to be achievable. These results demonstrate that SHINE can provide a high-performance BEUV source, offering a realistic pathway toward a high-average-power light source for next-generation high-resolution lithography.