All-Optical Encryption Controlled by Multiphotonic Absorption in Carbon Nanotubes

This study presents an all-optical approach based on an XOR logic gate for encryption by interference and the assistance of multiphotonic effects exhibited by carbon nanotubes. We integrate a Michelson interferometer to propose the encryption system. The key innovation lies in the use of multiwalled carbon nanotubes (MWCNT) to control the XOR operation through intensity-dependent nonlinear optical absorption. We introduce control based on nanosecond nonlinear optical absorption in MWCNT. By measuring irradiance propagation through thin-film samples of MWCNT, we demonstrate a threshold-based binary data recording system that is highly resistant to unauthorized access. The combination of interferometric response, MWCNT-based intensity control, and multicriteria decision analysis through nonlinear absorption presents a powerful and versatile approach to optical encryption. This method has the potential to be a base for secure communication systems and optical computing, with possible extensions to biological computing and microbiology. While challenges in power optimization and scaling remain, this research marks a significant step towards advanced, ultrafast encryption systems.