High-Performance Differential Imaging via Reconfigurable Black Phosphorus p-n Homojunction Optoelectronics

Area of Science:

• Materials Science
• Condensed Matter Physics
• Device Engineering

Background:

• Traditional photodetectors have static doping profiles, limiting dynamic signal modulation.
• Advancements in differential imaging and machine vision require hardware with adaptable signal control.

Purpose of the Study:

• To engineer a reconfigurable photodetector overcoming static limitations.
• To demonstrate dynamic band structure modulation in black phosphorus (BP).

Main Methods:

• Fabrication of a BP p-n homojunction photodetector.
• Utilized in situ ferroelectric domain programming with a bismuth ferrite substrate.
• Achieved reversible switching between p-n and n-p configurations via ferroelectric doping.

Main Results:

• Demonstrated non-volatile, nondestructive modulation of BP band structure.
• Achieved self-powered operation with 44 mA/W responsivity at 808 nm.
• Showcased a single-pixel imaging prototype with tunable edge sharpness and high-fidelity reconstruction.

Conclusions:

• Established a new paradigm for ferroelectrically programmable 2D devices.
• Developed a versatile platform for differential imaging and contrast enhancement.
• Ferroelectric doping offers a damage-free alternative to ion implantation for device programmability.