Broadband imaging spectrometer based on conical diffraction for extreme ultraviolet source

Area of Science:

• Optics and Photonics
• Spectroscopy
• Ultrafast Science

Background:

• Extreme ultraviolet (EUV) light sources, particularly those generated by high-harmonic lasers, are crucial for advanced research.
• Existing imaging spectrometers often face limitations in resolution, efficiency, or complexity when used with EUV sources.
• The need for aberration-free, high-performance spectral measurement tools in the EUV range is significant.

Purpose of the Study:

• To introduce a novel imaging spectrometer design for EUV sources.
• To demonstrate the aberration-free imaging capabilities of the proposed spectrometer.
• To evaluate the performance of the spectrometer in terms of efficiency, spectral resolution, and spectral coverage.

Main Methods:

• Design and implementation of a grating-toroid-grating spectrometer configuration.
• Utilizing uniformly spaced planar gratings for spectral analysis.
• Conducting detailed aberration analysis and data simulations.
• Experimental validation merging theoretical analysis with collected data.

Main Results:

• Demonstration of a novel, simple, and effective grating-toroid-grating imaging spectrometer for EUV.
• Achieved aberration-free point-to-point imaging across the entire working wavelength range.
• Optimized combination of high flux efficiency, sufficient spectral resolution, and broad spectral coverage.
• Experimental data aligned with theoretical simulations, confirming the spectrometer's performance.

Conclusions:

• The developed EUV imaging spectrometer represents a significant advancement in spectral measurement technology.
• Its aberration-free performance and high efficiency make it suitable for a wide range of scientific applications.
• The spectrometer enables ultrafast spectroscopic and pump-probe experiments with high temporal precision (femtosecond to picosecond).