# Optically programmable dual-band perovskite single-pixel detector for color image encryption

## TL;DR

A new color image encryption method uses a special photodetector that acts as both a detector and a decryption key to enhance security.

## Contribution

An optically programmable dual-band photodetector is introduced for secure color image encryption.

## Key findings

- The photodetector's sensitivity can be manipulated via short-wavelength stimulation.
- Different imaging outputs prevent eavesdropping when using other detectors.
- The method integrates imaging and decryption for enhanced encryption security.

## Abstract

The rapid evolution of eavesdropping technologies has encouraged regular updates and improvement of encryption systems. Developing a detector-dependent optical encryption scheme to tightly connect the decryption and imaging processes offers great potential to prevent eavesdropping. By designing an optically programmable dual-band photodetector, a color image encryption scheme where the photodetector functions as both a detector and a critical decryption key is demonstrated here. The distinctive optically programmable property of the photodetector enables the manipulation of its long-wavelength sensitivity via short-wavelength photonic stimulation, leading to different imaging outputs between single-pixel imaging and point-scan imaging, which therefore demonstrates a capability to decrypt information hidden in color images. This detector-dependent decryption method can effectively prevent potential information leaks when other detectors are used as eavesdropping devices. Our encryption paradigm opens new avenues for color image encryption using photodetectors, enhancing encryption security by introducing a device-based dimension.

Owing to different outputs between single-pixel imaging and point-scan imaging, an optically programmable dual-band perovskite photodetector enables a high-security detector-dependent color image encryption scheme by integrating imaging and decryption processes.