Semiconductor membrane microchip laser

Area of Science:

• Optics and Photonics
• Semiconductor Lasers
• Materials Science

Background:

• Semiconductor lasers are crucial for various applications.
• Compact, high-power laser sources with excellent beam quality are in demand.
• Membrane external-cavity surface-emitting lasers (MECSELs) offer a promising platform for advanced laser design.

Purpose of the Study:

• To demonstrate a novel semiconductor microchip membrane external-cavity surface-emitting laser (MECSEL).
• To investigate the performance characteristics, including output power, efficiency, and beam quality.
• To analyze the thermal properties and the dependence of the thermal lens on pump power.

Main Methods:

• Fabrication of a micron-thin semiconductor gain region membrane sandwiched between transparent heat spreaders.
• Assembly of a compact, plane-parallel solid-state laser cavity (∼1 mm length) with reflective coatings.
• Optical pumping using a fiber-coupled diode laser module (808 nm) and characterization of laser output.

Main Results:

• Demonstrated continuous wave output power exceeding 1 W at 1123 nm.
• Achieved a record slope efficiency of approximately 51.4% for MECSELs.
• Maintained excellent beam quality (TEM₀₀, M² < 1.05) and investigated polarization properties.

Conclusions:

• The developed microchip MECSEL is a highly efficient and compact laser source.
• This technology offers customizable emission wavelengths and high-power output with superior beam quality.
• The system's thermal properties were characterized, providing insights for further optimization.