With the world’s smallest QR code, scientists at TU Wien, together with the Austrian-German startup Cerabyte, succeeded in securing an entry in the Guinness World Records.
According to TU Wien, the QR code is smaller than many bacteria and visible only under an electron microscope. The technology could offer significant potential for long-term data storage. Conventional storage technologies often have only a short lifespan and require continuous energy, cooling, and regular data transfers.
Vienna Researchers Clearly Surpass QR Code Record
Ceramic thin films are used to coat high-performance tools in order to make them stable and durable under extreme conditions. “That is precisely what makes these materials ideal for data storage,” said Erwin Peck and Balint Hajas from the Thin Film Materials Science research group in a statement from TU Wien, where such materials are being studied. Using focused ion beams, the scientists milled the QR code into a thin ceramic layer—on an area of just 1.98 square micrometers.
The code consists of 29 by 29 modules, with individual pixels measuring only 49 nanometers. “They cannot be detected with light microscopes at all,” explained Paul Mayrhofer from the Institute of Materials Science and Technology at TU Wien. The code can be reliably read only with an electron microscope. The Vienna code clearly surpasses the current Guinness world record of 5.38 square micrometers (also with 29 by 29 modules and a pixel size of 80 nanometers).
“Remarkable Storage Capacity”
The small size of the code itself is not the most remarkable aspect; structures in the micrometer range, even patterns made of individual atoms, can be produced today. “But that does not yet result in a stable, readable code,” Mayrhofer said. Only the use of a stable material that hardly reacts with its environment, such as ceramic, makes it possible to store information almost indefinitely without energy input or cooling—and therefore in a climate-friendly way. The research team engraved its record code into a 15-nanometer-thick writing layer made of chromium nitride, which lies on a glass substrate.
Based on its size and number of modules, the record QR code achieves “an information density of 130 bits per square micrometer,” Erwin Peck told APA. In principle, the research team sees “remarkable storage capacity” in the method. On the surface area of a standard A4 sheet of paper, more than two terabytes of data could be stored in this way. The record for the smallest QR code was reviewed and officially recognized by Guinness World Records.
To make ceramic data storage suitable for industrial use, the research team plans to use additional materials, increase writing speed, and develop scalable manufacturing processes. The scientists are also investigating how more complex data structures—far beyond simple QR codes—can be written into ceramic thin films in a robust, fast, and energy-efficient manner and reliably read out.
