High efficiency and a narrow spectrum spectral beam combining a module with a single grating external cavity

Area of Science:

• Optics and Photonics
• Laser Technology
• Materials Science

Background:

• High-power lasers require efficient methods for combining multiple spectral beams.
• Conventional spectral beam combining (SBC) techniques face limitations in efficiency and spectral narrowing.
• Diffraction gratings are crucial components in optical systems for manipulating light.

Purpose of the Study:

• To propose and demonstrate a novel single grating multiple diffraction spectral beam combining (SBC) structure.
• To enhance the combining efficiency and spectral purity of high-power laser beams.
• To investigate the potential of this new SBC method for advanced laser systems.

Main Methods:

• Development of a single grating structure for multiple diffraction spectral beam combining.
• Implementation of polarization separation and full feedback mechanisms to maintain high efficiency.
• Experimental demonstration under continuous wave (CW) operation at a specific current (25 A).

Main Results:

• Achieved a maximum combining efficiency of 81.1%.
• Generated an output power of 12.3 W with a narrow spectrum width of 6.1 nm.
• Demonstrated significant improvements in combining efficiency: 6% over conventional SBC and 17.3% over double gratings SBC.

Conclusions:

• The proposed single grating multiple diffraction SBC method is a novel and effective technique.
• This approach offers a prospective solution for increasing combining efficiency in multi-diffraction SBC systems.
• The method shows promise for achieving narrow spectral output in high-power laser applications.