Ultra High-efficiency Integrated Mid Infrared to Visible Up-conversion System.

Area of Science:

• Optoelectronics
• Materials Science
• Solid-State Physics

Background:

• Mid-infrared (MIR) to visible light conversion is crucial for various applications.
• Existing methods often face limitations in efficiency and tunability.
• Integrated optoelectronic devices offer potential for compact and efficient solutions.

Purpose of the Study:

• To introduce and investigate an integrated optoelectronic chip for MIR to visible light up-conversion.
• To demonstrate a high-efficiency conversion process using novel device architecture.
• To explore the tunability of the device for different MIR wavelengths and visible outputs.

Main Methods:

• Fabrication of an integrated chip combining a PbSe nanocrystalline photoconductive layer, NPN bipolar junction transistor, and phosphorescent organic light-emitting diode (OLED).
• Utilizing a quantum dot photodetector for MIR light detection and an OLED for visible light emission.
• Characterization of the device's up-conversion efficiency and spectral properties.

Main Results:

• The proposed device successfully achieves up-conversion from MIR (3 μm) to visible green light (523 nm).
• High-efficiency conversion with an external quantum efficiency of 600% for 3 μm to 523 nm was achieved.
• The device demonstrates high flexibility, allowing tuning of both MIR detection (3-5 μm) and visible emission wavelengths.

Conclusions:

• The integrated optoelectronic chip offers a highly efficient and flexible solution for MIR to visible light up-conversion.
• Enhancements in transistor current gain (β) and alternative structures like Darlington can further boost conversion efficiency.
• This technology holds promise for advanced optical sensing and display applications.