MEMS-metasurface-enabled mode-switchable vortex lasers

Area of Science:

• Photonics and Laser Technology
• Microelectromechanical Systems (MEMS)
• Optical Metasurfaces

Background:

• Conventional lasers are limited to static modes, restricting flexibility in coherent light generation.
• Current mode-switchable lasers often rely on bulky and slow optical components, hindering practical applications.
• There is a need for compact, fast, and versatile laser sources capable of dynamic mode control.

Purpose of the Study:

• To demonstrate a fiber laser system capable of rapid switching between different laser modes.
• To integrate microelectromechanical system (MEMS)-based optical metasurfaces (OMS) into a laser cavity for mode control.
• To achieve high-purity Gaussian and vortex laser modes with electrical tunability.

Main Methods:

• Fabrication of an intracavity microelectromechanical system (MEMS)-based optical metasurface (MEMS-OMS).
• Integration of the MEMS-OMS into a fiber laser cavity operating at ~1030 nm.
• Electrical actuation of the MEMS mirror to control laser mode output (Gaussian and vortex modes).

Main Results:

• Successful demonstration of mode switching between fundamental Gaussian (l=0) and vortex (l=1, 2, 3, 5) laser modes.
• Achieved high mode purities exceeding 95% for all demonstrated modes.
• Exhibited fast switching response times of approximately 100 microseconds.

Conclusions:

• The proposed intracavity MEMS-OMS-enabled fiber laser offers an at-source solution for generating fast-switchable, high-purity laser modes.
• This technology significantly enhances the flexibility and versatility of coherent light sources compared to conventional lasers.
• Potential applications include advanced optical imaging, optical tweezers, optical machining, and intelligent photonics.