Conversion of a TEM10 beam into two nearly Gaussian beams

Area of Science:

• Optics
• Laser Physics
• Photonics

Background:

• High-power laser systems often utilize high-order or multiorder transverse modes for increased output power and efficiency.
• Operating with these modes, however, significantly compromises beam quality, limiting applications that require a well-defined beam profile.
• The Hermite-Gaussian TEM(10) mode is a common example of a higher-order mode characterized by two distinct lobes.

Purpose of the Study:

• To introduce and analyze a novel technique for converting a Hermite-Gaussian TEM(10) beam into multiple TEM(00) beams.
• To quantify the power conversion efficiency and assess the improvement in beam quality.
• To demonstrate a practical method for enhancing laser beam quality from higher-order modes.

Main Methods:

• A technique involving spatial separation of the two lobes of a TEM(10) beam using an edge aperture is proposed.
• The spatial overlap between a lobe of the TEM(10) beam and an appropriately selected TEM(00) beam is calculated.
• A single-mode optical fiber is employed as a spatial filter to remove any residual higher-order mode content.

Main Results:

• Nearly 94% of the power within a single lobe of the TEM(10) beam can spatially overlap with a suitable TEM(00) beam.
• Separating the TEM(10) lobes with an edge aperture effectively increases the beam quality, measured by the M(2) factor.
• The proposed method demonstrates the potential to convert over 90% of the total power from a TEM(10) beam into two separate TEM(00) beams.

Conclusions:

• The developed technique offers an effective way to improve the beam quality of high-power laser systems.
• This method allows for the efficient conversion of higher-order TEM(10) modes into multiple high-quality TEM(00) beams.
• The findings suggest a viable approach for enhancing laser performance in applications demanding high beam quality and significant power.