Anisotropic PdSe₂/GeAs Heterostructures with Switchable Photocurrent Polarity for Polarization Imaging and...

Area of Science:

• Materials Science
• Nanotechnology
• Optoelectronics

Background:

• Stacking 2D materials offers potential for multifunctional optoelectronic devices.
• Anisotropic 2D materials provide enhanced control over in-plane photoelectric properties.
• Limited research exists on stacking anisotropic 2D materials for complex device applications.

Purpose of the Study:

• To fabricate and investigate an anisotropic PdSe2/GeAs heterojunction for multifunctional optoelectronic applications.
• To explore the self-driven photodetection and polarization imaging capabilities of the heterojunction.
• To demonstrate programmable photonic logic gate functions using electrical and optical control.

Main Methods:

• Fabrication of an anisotropic PdSe2/GeAs heterojunction.
• Characterization of the device's self-driven photodetection performance (responsivity, detectivity, EQE).
• Evaluation of high-resolution polarization imaging and image convolution processing.
• Investigation of photocurrent polarity switching via gate voltage.
• Demonstration of multi-state logic outputs and photonic logic gates.

Main Results:

• The PdSe2/GeAs heterojunction exhibited self-driven performance with high responsivity (680 mA/W), detectivity (1.1 × 10^11 Jones), and EQE (158%).
• The device achieved high-resolution polarization imaging and image convolution.
• Photocurrent polarity was switchable with gate voltage, enabling multi-state logic outputs.
• Programmable photonic logic gate functions were successfully demonstrated.

Conclusions:

• The anisotropic PdSe2/GeAs heterojunction is a promising platform for multifunctional optoelectronic devices.
• This work offers insights into developing integrated systems based on anisotropic heterostructures.
• The findings pave the way for intelligent optical sensing and high-speed optical communication.