Van de Graaf-based 13.5 nm inverse-Compton light source

Abstract

We review the factors governing the performance of inverse-Compton light sources in the extreme-ultraviolet (EUV) region. While the use of an optical storage cavity and the minimization of the laser pump focal spot area remain critical to the optimization of power and brightness in the EUV, the appearance of a strong space charge forces at the low electron energies required for operation in the EUV sets an independent lower limit to the focal spot area, and therefore an upper limit to source power and brightness. These limitations are at least partially compensated by the very high average electron currents realizable at these lower electron energies. Based on these considerations, we describe the design and estimated performance of an EUV inverse-Compton scattering light source optimized for average power output and brightness consistent with the limits imposed by the capabilities of existing materials, laser pumps, and radio frequency power sources.