Extreme ultraviolet broadband imaging spectrometer using dispersion-matched zone plates

Area of Science:

• Optics and Photonics
• Plasma Physics
• Spectroscopy

Background:

• Laser-produced plasmas (LPPs) are crucial sources for extreme ultraviolet (EUV) light generation.
• Characterizing LPPs requires advanced diagnostic tools for spatial and spectral analysis.
• Existing methods may lack the simultaneous imaging and broadband spectroscopy capabilities needed for comprehensive analysis.

Purpose of the Study:

• To present a novel device for simultaneous 1D imaging and broadband spectroscopy of EUV light.
• To detail the design and fabrication of a tapered zone plate matched to a transmission grating.
• To benchmark the performance of the developed imaging spectrometer using an LPP source.

Main Methods:

• Simultaneous 1D imaging and broadband spectroscopy were performed on an LPP source.
• A tapered zone plate, designed for the 5-80 nm wavelength range, was coupled with a transmission grating.
• The device achieved a spatial resolution of approximately 10 µm and a spectral resolution of approximately 0.8 nm.
• Plane wave propagation simulations were used to validate experimental observations.

Main Results:

• The developed zone plate successfully enabled simultaneous 1D imaging and spectroscopy.
• The device demonstrated a spatial resolution of ~10 µm and spectral resolution of ~0.8 nm in the 5-80 nm regime.
• Experimental results were qualitatively corroborated by plane wave propagation simulations.

Conclusions:

• The novel tapered zone plate and transmission grating combination provides effective simultaneous 1D imaging and broadband spectroscopy of EUV LPPs.
• The device meets designed spatial and spectral resolution targets, offering a valuable diagnostic tool.
• The findings confirm the device's performance and potential for characterizing EUV sources.