Mid-Infrared Lasing in Lead Sulfide Subwavelength Wires on Silicon.

Area of Science:

• Semiconductor Nanowire Growth
• Mid-Infrared Photonics
• Integrated Photonics

Background:

• Vapor-liquid-solid (VLS) growth produces high-quality nanowires for photonic applications across various wavelengths.
• Current VLS lasing demonstrations are primarily limited to ultraviolet and visible wavelengths, with few in the short-wavelength infrared.
• Extending lasing to mid-infrared (MIR) wavelengths faces challenges due to decreased radiative efficiency and material limitations.

Purpose of the Study:

• To demonstrate lasing in the mid-infrared (MIR) range using subwavelength semiconductor wires.
• To overcome the limitations of existing materials and achieve MIR lasing on a silicon platform.
• To explore the potential of lead sulfide (PbS) nanowires for MIR photonic applications.

Main Methods:

• Utilized vapor-liquid-solid (VLS) growth for high-quality lead sulfide (PbS) nanowire fabrication.
• Integrated PbS nanowires onto silicon substrates for on-chip photonic applications.
• Demonstrated lasing from individual PbS nanowires in the MIR spectrum (3-4 μm).

Main Results:

• Achieved MIR lasing from single PbS nanowires on both silicon and transferred sapphire substrates.
• Demonstrated lasing in wires with sizes below half the normalized volume.
• Observed lasing operation at temperatures up to 180 K.

Conclusions:

• Successfully demonstrated MIR lasing from subwavelength PbS nanowires on silicon.
• This achievement opens possibilities for integrated MIR photonic devices on silicon platforms.
• Subwavelength MIR wire lasers are promising for applications in sensing, communications, and beyond.