Highly Sensitive Room-Temperature Graphene-Modulated AlGaN/GaN HEMT THz Detector Architecture

Area of Science:

• Semiconductor device physics
• Terahertz (THz) technology
• Graphene-based electronics

Background:

• Terahertz (THz) radiation detection is crucial for various applications.
• Existing THz detectors often require cryogenic cooling, limiting their practicality.
• Developing room-temperature (RT) THz detectors with high sensitivity is a significant challenge.

Purpose of the Study:

• To propose and simulate a novel architecture for a highly sensitive graphene-gated AlGaN/GaN HEMT THz detector.
• To enable efficient THz detection at room temperature.
• To investigate the underlying physical mechanisms for enhanced THz detection.

Main Methods:

• Analytical modeling and computer-aided design (CAD) simulations were employed.
• A monolayer graphene gate was designed as a surface plasmon absorber.
• The HEMT structure featured a partially depleted 2DEG channel for enhanced mobility and nonlinearity.

Main Results:

• The proposed detector architecture demonstrates high sensitivity.
• Simulations predict a responsivity of 2.12 × 10^6 V/W at 1 THz.
• A broadband detection bandwidth of 2 THz was achieved.

Conclusions:

• The novel graphene-gated HEMT architecture enables efficient room-temperature THz detection.
• Reduced phonon losses due to Drude absorption in graphene are key to RT operation.
• The proposed detector shows significant potential for future THz sensing and imaging systems.