Bias-Tunable Plasmonic Ga₂O₃/GaN Photodetectors for Reconfigurable Logic, Encryption, and Ultraviolet Imaging

Area of Science:

• Materials Science
• Optoelectronics
• Nanotechnology

Background:

• Gallium Oxide/Gallium Nitride (Ga2O3/GaN) heterojunctions are cost-effective for UV detection.
• High driving voltages limit their near-UV (365 nm) performance due to top layer transparency.

Purpose of the Study:

• To develop a high-performance dual-band UV photodetector with enhanced sensitivity and low-voltage operation.
• To demonstrate reconfigurable optoelectronic logic gates and UV imaging/encryption capabilities within a single device.

Main Methods:

• Fabrication of a Ga2O3/GaN heterojunction decorated with silver nanoparticles (Ag NPs) via solid-state dewetting.
• Utilizing the localized surface plasmon resonance (LSPR) effect of Ag NPs for dual-gain detection.
• Implementing bias-tunable spectral response for reconfigurable logic gates.

Main Results:

• Achieved enhanced solar-blind (254 nm) responsivity via local field amplification.
• Enabled sensitive 365 nm detection at low bias through hot-electron injection.
• Successfully constructed reconfigurable optoelectronic logic gates (OR, NOR, XNOR) in a single device.
• Demonstrated a basic optical encryption scheme and dual-color UV imaging.

Conclusions:

• The Ag NP-decorated Ga2O3/GaN heterojunction offers a strategy for low-power, high-performance UV detection.
• This approach enables intelligent, secure, and in-sensor computing optoelectronic systems.
• Paves the way for advanced UV sensing and processing applications.