Self‐Erase Force‐Induced Turn‐On Organic ASE Output Cryptographic Primitive for Advanced Multiple Information Encryption

Abstract

The development of high density and security information encryption system, in particular narrowband luminescence cryptographic primitive, is of notable significance but extremely challenging for anticounterfeiting applications. Herein, a novel piezochromic fluorescent (PCF) molecule 4‐(4‐(4‐methylpiperazin‐1‐yl)styryl)‐N,N‐diphenylaniline (TPIZ) is reported, which features high pressure sensitivity and self‐erase force‐induced amplified spontaneous emission (ASE) output multicolor switching. The remarkable green/cyan photoluminescence emission and blue ASE emission of TPIZ microcrystals can be switched reversibly under pressure and pumping energy. A mechanistic study of X‐ray diffraction analysis reveals that the rotation of the C═C bond under low pressure caused the reduction of the weak intermolecular interaction, which is responsible for its excellent PCF performances with self‐erase features. Moreover, the force‐induced amplification of ASE output behaviors are observed due to the high quality of TPIZ microcrystals. Benefiting from the pressure sensitivity, ASE emission as well as self‐erase behaviors of TPIZ microcrystals, a triple encoding self‐erase system is developed for advanced information encryption. This work can provide a crucial step toward the force‐induced narrowband ASE cryptographic primitive materials for high level security application.

Quantum Dots‐Functionalized Encryption Camera for Text Image Security Protection

“…[ 3,33–36 ] optical encryption, [ 3,37 ] and fluorescent material‐based encryption, [ 5–8 ] the execution time (ET) of QDE camera is mainly determined by the exposure time (0.025–0.032 s), providing great advantage of high‐speed image encryption. [ 3,33–36 ] The QDE camera was further evaluated by comparing its performance with the previous reported encryption techniques, [ 3,5–8,33–37 ] including statistical analysis of digital image (histogram analysis, information entropy, and correlation coefficient) [ 3,27 ] and peak signal‐to‐noise ratio (PSNR) between decrypted image and original image. [ 3,27,33,36 ] Table 2 shows the comparison between QDE camera with chaotic cryptosystem, [ 3,33–36 ] optical encryption, [ 3,37 ] and fluorescent material‐based encryption.…”

“…[ 3,27,33,36 ] Table 2 shows the comparison between QDE camera with chaotic cryptosystem, [ 3,33–36 ] optical encryption, [ 3,37 ] and fluorescent material‐based encryption. [ 5–8 ]…”

“…[ 2 ] It is very necessary to encrypt the text image for security protection. [ 3,4 ] To our knowledge, there are three typical ways to achieve image encryption, including fluorescent material‐based encryption, [ 5–8 ] computer cryptology, [ 9–13 ] and optical encryption, [ 14–21 ] while these techniques hardly satisfy the high‐speed encryption requirements of information acquisition and online communication. The information encryption using fluorescent materials is limited to hard copy such as paper‐based images.…”

“…[ 13 ] Quantum dots (QDs) are color‐tunable fluorescent materials with easy patterning operation, enabling them to spatially tune the light intensity and colors of photoluminescence emission. [ 5–8,14,28–31 ] Herein, we propose QD‐ functionalized encryption (QDE) camera to combine the information encryption with the image acquisition by integrating the fluorescence emission of QDs to scramble the spatial distribution of RGB values in the captured images of CCD or CMOS device during the imaging process. It expands the information entropy of the captured images to realize high‐speed in situ image encryption.…”

Tunable near-infrared piezochromic luminescence by effective substituent modification of D–A structures

“…Piezochromic luminescent (PCL) materials have attracted extensive research interest due to their potential applications in information encryption, optical glasses, electric displays, optoelectronic devices, etc. [1][2][3][4][5][6][7][8][9] The emission color of these materials changes in response to external mechanical stimuli such as grinding, scraping, pressing, and stretching. [10][11][12] The main mechanism of piezochromism includes phase transition, chemical structure change, and excited-state transformation.…”