High-power radially polarized Yb:YAG thin-disk laser with high efficiency

Area of Science:

• Laser Physics
• Optics
• Materials Science

Background:

• Radially polarized beams are crucial for applications like particle acceleration and microscopy.
• Achieving high power and high efficiency in radially polarized beams remains a challenge.
• Thin-disk laser architectures offer advantages for high-power operation.

Purpose of the Study:

• To generate high-power radially polarized beams from an Ytterbium-doped Yttrium Aluminum Garnet (Yb:YAG) thin-disk laser.
• To design and fabricate a polarization-selective intra-cavity component.
• To characterize the performance of the generated beams and the novel optical element.

Main Methods:

• Utilized an Yb:YAG thin-disk laser.
• Incorporated an intra-cavity circular resonant waveguide grating as a polarization selective mirror.
• Fabricated the grating using a scanning beam interference lithography system.
• Measured output power, beam quality (M2), and efficiency.

Main Results:

• Generated radially polarized beams with 275 W output power.
• Achieved a beam quality factor (M2) of 2.3.
• Obtained an overall laser efficiency of approximately 52.5%.
• Demonstrated the functionality of the polarizing grating mirror.

Conclusions:

• Successfully generated high-power radially polarized beams from a Yb:YAG thin-disk laser.
• The intra-cavity waveguide grating is an effective component for polarization control in lasers.
• The demonstrated technology shows promise for advanced laser applications requiring radial polarization.