Intracavity generation of radially polarized CO2 laser beams based on a simple binary dielectric diffraction grating

Area of Science:

• Laser Physics
• Optics and Photonics
• Materials Science

Background:

• Radially polarized light offers unique properties for various applications.
• Generating high-purity radially polarized beams, especially in industrial lasers like CO2, remains a challenge.
• Existing methods often involve complex setups or lower purity levels.

Purpose of the Study:

• To demonstrate a simple and effective method for intracavity generation of radially polarized light in a CO2 laser.
• To achieve high polarization selectivity using a novel mirror design.
• To validate experimental results with theoretical simulations.

Main Methods:

• Incorporation of a polarization-selective mirror within a CO2 laser resonator.
• Fabrication of the selective mirror using a binary dielectric diffraction grating etched on the substrate's backsurface.
• Characterization of the generated beam's polarization purity.

Main Results:

• Successful generation of radially polarized light within the CO2 laser cavity.
• Achieved very high polarization selectivity with the diffraction grating mirror.
• Experimental results showed good agreement with simulation predictions.
• The generated laser beam exhibited an overall radial polarization purity exceeding 90%.

Conclusions:

• The developed polarization-selective mirror is a highly effective component for intracavity generation of radially polarized light.
• This method offers a straightforward approach to obtaining high-purity radially polarized beams from CO2 lasers.
• The findings pave the way for advanced applications requiring radially polarized light in the infrared spectrum.