A High Spatial and Depth Resolution Deep-UV 266 nm Wavelength Laser-Based Integrated LIBS, Fluorescence, and Raman...

Area of Science:

• Spectroscopy
• Geochemistry
• Planetary Science

Background:

• Accurate elemental and molecular analysis of geological materials is crucial for planetary exploration and material science.
• Existing spectroscopic methods may lack the required resolution, portability, or multifunctionality for in-situ analysis.
• Deep-ultraviolet (UV) laser spectroscopy offers potential for high-resolution analysis of diverse materials.

Purpose of the Study:

• To develop and evaluate an integrated deep-UV laser-induced breakdown spectroscopy (LIBS), fluorescence, and Raman (LFR) system.
• To achieve high spatial and depth resolution for qualitative probing of lunar and planetary simulants and geological materials.
• To establish a foundation for compact, multifunctional spectroscopic systems for space and terrestrial applications.

Main Methods:

• Development of a compact LFR optical head (6 cm × 3 cm × 5 cm) utilizing a single 266 nm deep-UV pulsed laser source.
• Integration of LIBS, fluorescence, and Raman spectroscopy capabilities using a shared spectrometer.
• Achieved spatial resolution of approximately 15 μm (reducible to sub-μm) and submicron depth resolution.
• Probed standard organic/inorganic materials, simulants, and geological samples (silicates, oxides).

Main Results:

• The integrated LFR system successfully performed qualitative analysis of diverse materials.
• LIBS analysis accurately identified major elements (Mg, Si, Fe, Al, Ca, Mn, Ti) in geological samples and simulants.
• Raman spectroscopy effectively detected organic (alcohols, alkanes, amino acids, polymers) and inorganic (sulfates, carbonates) species.
• Obtained LIBS spectra showed good agreement with literature data, with no significant compositional variations observed with depth or spatial position.

Conclusions:

• The developed deep-UV LFR system provides a versatile and high-resolution platform for analyzing geological and simulant materials.
• The system's compact design and multifunctional capabilities pave the way for miniaturized spectroscopic instruments for in-situ planetary and material analysis.
• This work demonstrates the potential of single laser-spectrometer systems for combined Raman, LIBS, and fluorescence analysis.