Photo-Tailored Band Engineering for Optoelectronic Logic Gates via In -Situ Grown SnS/SnS₂ Heterojunction

Area of Science:

• Optoelectronics
• Materials Science
• Nanotechnology

Background:

• Optoelectronic logic gates (OELGs) are crucial for advanced computing architectures.
• Current OELGs face challenges in achieving multiple logic functions on a single device due to unidirectional carrier transport.

Purpose of the Study:

• To design and demonstrate a novel OELG photodetector capable of performing multiple reconfigurable logic functions.
• To overcome limitations of traditional heterojunctions by enabling reversible carrier transport.

Main Methods:

• Fabrication of a SnS/SnS2 lateral heterojunction via in situ-grown sulfidation technology.
• Phototailored band engineering to achieve wavelength-dependent bipolar photoresponse.
• Demonstration of seven basic logic functions and composite logic operations.

Main Results:

• The device exhibits ultrafast, repeatable, and wavelength-dependent bipolar photoresponse.
• Achieved superior optoelectronic performance: D* = 1.5 × 10^11 Jones, R = 43.5 mA/W, response speed of 16.8 ms, and on/off ratio of 1675.
• Successfully demonstrated seven reconfigurable logic functions (AND, OR, NOT, NAND, NOR, XOR, XNOR) and composite logic operations on a single photodetector.
• Implemented an ultraprecision optical communication system with a bit error rate <10^-6.

Conclusions:

• The developed SnS/SnS2 heterojunction photodetector offers a novel strategy for reconfigurable OELGs.
• This work opens new avenues for intelligent optoelectronics and next-generation light computing applications.