Dimension-Controlled VO₂ Film for Optoelectronic Logic Gates and Information Encryption

As the fields of photonics and information technology develop, a lot of novel applications based on VO₂ material, such as optoelectronic computing and information encryption, have been developed. While the performance of these devices was not only closely associated with the VO₂ phase transition properties but also depended on their dimensional characteristics. In the current study, we conducted the dimension-controlled vanadium dioxide (VO₂) film growth, resulting in the epitaxial 2-dimensional (2D) VO₂ film and well-distributed 3-dimensional (3D) VO₂ crystal film deposition, respectively. It was revealed that, unlike the 2D film, the pronounced localized surface plasmon resonance dominated the near-infrared spectrum across the phase transition for the 3D VO₂ film due to the naturally formed meta-surface structure, which showed a transmittance valley in the infrared spectrum after metallization. Based on this distinct infrared spectrum feature in the 3D VO₂ film, we proposed an optoelectronic logic gate controlled by the input voltage and the probing Vis/IR light. By detecting the transmittance states of the probing light with different wavelengths, we achieved multistate encoding functions and demonstrated the information encryption application. This new conception device also showed great potential for some other applications such as optoelectronic coupled computing, information encryption, and optical near-field sensing computing.