Self-Powered Au/ReS₂ Polarization Photodetector with Multi-Channel Summation and Polarization-Domain Convolutional...

Area of Science:

• Materials Science
• Optoelectronics
• Nanotechnology

Background:

• Conventional polarization imaging requires bulky, power-hungry external optics.
• A pixel-level approach for polarization encoding and readout is highly desirable for compact and efficient imaging systems.
• Low-symmetry layered semiconductors offer inherent anisotropy for polarization selectivity.

Purpose of the Study:

• To develop a compact, zero-bias pixel for polarization imaging.
• To achieve enhanced signal amplitude and stability in polarization-resolved measurements.
• To establish a general pixel-level foundation for scalable polarization cameras and computational sensing.

Main Methods:

• Fabrication of an eight-terminal radial 'star-shaped' gold/rhenium disulfide (Au/ReS2) metal-semiconductor junction array pixel.
• Operation in photovoltaic mode under zero external bias utilizing the photothermoelectric effect.
• Electrical summation of phase-matched multi-junction channels for signal amplification ('gain by stacking').

Main Results:

• Demonstration of a zero-bias, photovoltaic operation of the Au/ReS2 pixel.
• Achieved signal amplitude increase with electrical summation without sacrificing modulation depth.
• Exhibited millisecond-scale transient response and robust cycling stability.
• Successful realization of polarization-resolved imaging and pattern recognition at the pixel level.

Conclusions:

• The developed star-shaped Au/ReS2 pixel provides a compact, low-noise, and scalable solution for polarization imaging.
• The 'gain by stacking' approach enables signal amplification without external components.
• This work lays the foundation for advanced polarization cameras and on-pixel computational sensing applications.