Photogating Effect-Driven Photodetectors and Their Emerging Applications

Area of Science:

• Optoelectronics
• Semiconductor Physics
• Materials Science

Background:

• The photoelectric effect relies on photo-excited carriers, limiting detection to energies above the bandgap.
• The photogating effect utilizes trapped photo-induced charges to modulate semiconductor interfaces.
• This modulation creates an electrical gating field, shifting threshold voltage and enabling sub-bandgap detection.

Purpose of the Study:

• To review photodetectors driven by the photogating effect.
• To discuss emerging optoelectrical materials, device structures, and mechanisms.
• To highlight applications and future challenges of photogating effect-based devices.

Main Methods:

• Review of existing literature on photogating effect-driven photodetectors.
• Analysis of representative examples of sub-bandgap photodetection.
• Discussion of material properties, device architectures, and operational mechanisms.

Main Results:

• The photogating effect provides a clear separation of drain current in dark and bright conditions.
• It enables the detection of sub-bandgap rays, overcoming limitations of the photoelectric effect.
• Various emerging materials and device structures have demonstrated this effect.

Conclusions:

• Photogating effect-driven photodetectors offer a promising route for sub-bandgap photodetection.
• Further research into materials, device optimization, and novel applications is warranted.
• Addressing challenges will pave the way for next-generation photodetector technologies.