Published on 29 Mar 2023

Lasers for secure communication

Encoding information using biological lasers.

Binary code background

The world generates approximately 2.5 quintillion bytes of data every day. Amid this explosion in information, several information encryption, anti-counterfeiting and secure communication technologies have emerged.

Taking advantage of sensitive enzyme-based reactions, NTU researchers led by Nanyang Asst Prof Chen Yu-Cheng of NTU’s School of Electrical and Electronic Engineering and School of Chemistry, Chemical Engineering and Biotechnology have developed a new method of encoding information using biological lasers.

The scientists generated the lasers by shining light through droplets of alginate – a polymer obtained from seaweed – that were sandwiched in a cavity known as a Fabry- Pérot microcavity. Then, the researchers used an enzyme called alginate lyase to degrade the alginate. This caused the droplets to swell, shifting the wavelengths of the emitted laser.

By controlling the rate of the reaction and size of the droplet, scientists could use the lasers to encrypt information that was revealed only under certain environmental stimuli, such as a change in humidity.

“The integration of biology with photonics paves the way for novel applications in secure communication and smart sensing,” says Nanyang Asst Prof Chen.

"Research into developing bioprogrammable lasers remains an important step in the future of these applications.”

The article “Enzyme-programmable microgel lasers for information encoding and anti-counterfeiting” was featured on the front cover of the March issue of Advanced Materials (2022), DOI: 10.1002/adma.202107809.


The article appeared first in NTU's research & innovation magazine Pushing Frontiers (issue #21, December 2022).