Electrically controlled enhancement in plasmonic mid-infrared photodiode

Area of Science:

• Optoelectronics
• Plasmonics
• Semiconductor Devices

Background:

• Surface plasmon polaritons (SPPs) enable deep subwavelength electromagnetic wave localization, crucial for advanced optoelectronic devices.
• Existing plasmonic devices face challenges in performance control and tunability.

Purpose of the Study:

• To propose and investigate a mid-infrared InAsSb-based n-i-p photodiode with electrically controlled photocurrent enhancement.
• To explore the tunability of SPP overlap with the absorption layer for performance optimization.

Main Methods:

• Fabrication of an InAsSb-based n-i-p photodiode.
• Utilizing SPPs for enhanced light-matter interaction within the photodiode.
• Electrically controlling the overlap between SPP depth and the absorption layer.

Main Results:

• Achieved maximum electrically controlled enhancement factors of ~5x at 293 K and ~6x at 77 K.
• Obtained electrical tuning factors of 11.9 and 26 at 293 K and 77 K, respectively.
• Reached maximum detectivities of 0.8 × 10^10 Jones (293 K) and 5 × 10^11 Jones (77 K).

Conclusions:

• The proposed photodiode demonstrates significant electrically controlled photocurrent enhancement.
• This electrical tunability expands the application capabilities of plasmonic photodiodes in optoelectronics.