We study a discharge supported by infrared laser in a high-pressure xenon jet. In the discharge, plasma with multiply charged xenon ions is generated that emit extreme-ultraviolet light (EUV light) near 11-nm wavelength demanded for modern lithography. This plasma, initially arising in a hot spot formed in the laser focus, may propagate and expand due to photoionization of surrounding gas and subsequent electron heating via conductive thermal flux from the laser focus. As a result, the xenon ions outside the laser focus get the opportunity to emit target EUV light. We report an experiment aimed to observe this effect. For the discharge in the xenon jet, the region that emits at $11.25\pm 0.08\mathrm{nm}$ is visualized by means of the dedicated EUV microscope based on Schwarzschild’s dual-reflector design, which incorporates multilayer Bragg mirrors. The EUV signal is registered both from within and from outside the laser focal spot, confirming that the plasma with multiply charged xenon ions expands outside the laser focus. The spatial structure of the discharge is observed that aligns with the theory previously developed by the authors.

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• Plasma production & heating by laser beams, laser-foil, laser-cluster
• Radiation & particle generation in plasmas
• XUV generation
• Bragg structures
• Laser systems
• Low-temperature plasma
• Optical sources & detectors
• Lithography