Graphene-based polarization-sensitive longwave infrared photodetector.

Area of Science:

• Optoelectronics
• Materials Science
• Nanotechnology

Background:

• Photodetectors are crucial for various sensing applications.
• Developing polarization-sensitive and broadband detectors is essential for advanced optical systems.
• Graphene's unique electronic and optical properties make it a promising material for photodetector applications.

Purpose of the Study:

• To theoretically demonstrate a novel polarization-sensitive photodetector based on periodically crossed graphene ribbons.
• To investigate the broadband detection capabilities and photoresponsivity of the proposed device.
• To explore the tunability of the photodetector's performance.

Main Methods:

• Theoretical demonstration using periodically crossed graphene ribbons.
• Utilizing localized surface plasmon resonance for enhanced light absorption.
• Employing finite difference time domain (FDTD) solutions for performance prediction.
• Modulating graphene's chemical potential via gate voltage for tunability.

Main Results:

• Achieved broadband detection from 10.5 to 16.5 μm.
• Observed high photoresponsivity up to 1.717 A W⁻¹ at 12.58 μm for 0° polarization.
• Demonstrated significant polarization sensitivity with photoresponsivity of 0.212 A W⁻¹ at 90° polarization.
• Showcased tunability by adjusting gate voltage.

Conclusions:

• The proposed polarization-sensitive, tunable, and broadband graphene photodetector shows significant potential for high-performance longwave infrared (LWIR) detection at room temperature.
• The patterned graphene structure enables enhanced light absorption via localized surface plasmons.
• This work offers a promising direction for future LWIR sensing technologies.