Generation of collimated far-ultraviolet (FUV) light using the laser-produced metal plasma

Laser-produced plasma is a promising compact light source applicable in a broad range of wavelengths. We performed a spectroscopic analysis and plasma characterization of the laser-produced plasma of Al, Fe, Cu, and Inconel alloy (Ni/Cr/Fe) to explore their potential applications in the far-ultraviolet (FUV) region where these methods are yet widely exploited. The emission spectrum from each target exhibited a characteristic spectral profile over the wavelength range from 120 to 250 nm. These results were well reproduced by spectral simulations, providing detailed information on the plasma. We also developed a dedicated parabolic mirror that successfully collimated the plasma radiation into beam with an intensity enhanced by a factor of ∼35. Our study demonstrated the generation of collimated FUV radiation with an intensity of a 107 photons/pulse/1% bandwidth as a potent laboratory-size light source for various applications.