Optically pumped 5 microm IV-VI VECSEL with Al-heat spreader

Area of Science:

• Optics and Photonics
• Semiconductor Lasers
• Mid-Infrared Technology

Background:

• Vertical external cavity surface emitting lasers (VECSELs) are crucial for various optical applications.
• Developing VECSELs in the mid-infrared spectrum presents unique material and design challenges.
• Efficient heat dissipation is critical for high-power and continuous-wave (CW) operation of VECSELs.

Purpose of the Study:

• To realize mid-infrared VECSELs operating at a 5 micrometer wavelength.
• To investigate simple active region designs for improved performance.
• To enhance thermal management for increased output power and operating temperature.

Main Methods:

• Fabrication of VECSELs utilizing PbTe gain layers within Pb(1-x)Eu(x)Te barriers.
• Employment of epitaxial Pb(1-y)Eu(y)Te/BaF(2) Bragg mirrors for cavity formation.
• Integration of an aluminum layer for improved heat dissipation.

Main Results:

• Achieved mid-infrared VECSELs with a 5 micrometer emission wavelength.
• Observed pulsed output power up to 300 mW(p) and CW output power of 3 mW at 100 K.
• Attained a maximum quantum efficiency of 14% and lasing up to 175 K.

Conclusions:

• The developed VECSELs demonstrate promising performance for mid-infrared applications.
• Simple active region designs and effective thermal management contribute to enhanced laser characteristics.
• The ability to operate at elevated temperatures broadens the potential use cases for these devices.