Tunable optically pumped lead-chalcogenide mid-infrared emitters on Si-substrates

Area of Science:

• Materials Science
• Optoelectronics
• Semiconductor Physics

Background:

• Mid-infrared (mid-IR) emitters are crucial for various applications, including gas sensing, free-space communications, and medical diagnostics.
• Developing efficient and tunable mid-IR sources remains a significant challenge in optoelectronics.

Purpose of the Study:

• To develop novel lead-chalcogenide mid-IR emitters using molecular beam epitaxy (MBE).
• To investigate the performance of double heterostructure (DH) and quantum well (QW) lasers.
• To demonstrate a "wavelength transformer" for frequency conversion in the mid-IR range.

Main Methods:

• Epitaxial growth of PbSe/PbEuSe heterostructures on Si or BaF(2) substrates via MBE.
• Optical pumping of DH and QW lasers using low-cost III-V laser diodes.
• Characterization of emission properties, including wavelength tuning via temperature and mechanical methods.
• Design and fabrication of a resonant cavity "wavelength transformer" with Bragg mirrors.

Main Results:

• Achieved mid-IR emission in the 3-6 micrometer range with output powers up to 200 mW.
• Demonstrated tunable emission by temperature control and mechanical adjustments.
• Successfully operated a "wavelength transformer" at room temperature, converting 0.8 micrometer pump radiation to 4.2 micrometer emission.
• Emission line characteristics (width and value) were found to be design-dependent.

Conclusions:

• Novel lead-chalcogenide mid-IR lasers and wavelength transformers can be effectively fabricated using MBE.
• These devices offer promising solutions for tunable mid-IR light generation.
• The demonstrated wavelength transformer presents a viable method for frequency conversion in the mid-IR spectrum.