How small can a QR code be? A team of researchers has pushed the limits to the extreme, creating one so small that it can only be detected using an electron microscope. Scientists at the Vienna University of Technology, in collaboration with data storage company Theravite, have created a QR code that measures just 1.98 square micrometers, smaller than most bacteria. This achievement has now been officially confirmed and recorded in the Guinness Book of Records.
Beyond its scale, this breakthrough could have a major impact on long-term data storage. Traditional storage technologies such as magnetic drives and electronic systems tend to degrade within a few years. In contrast, encoding information into ceramic materials could potentially preserve the information for hundreds or even thousands of years.
Stable reading possible at nanoscale
“The structures we create here are so minute that they cannot be seen at all with an optical microscope,” says Professor Paul Meyerhofer of the Institute of Materials Science at the Vienna University of Technology. “But that’s not really the remarkable part. Micrometer-scale structures are not uncommon today. It’s even possible to create patterns made of individual atoms. But that alone doesn’t result in a stable, readable code.”
At very small scales, atoms can move positions or fill gaps, potentially erasing stored data. “What we’ve done is fundamentally different,” Meyerhofer explains. “We created a small, stable, and repeatable QR code.”
Ceramic material allows for durable data storage
The key to this result lies in the material itself. “We are working on ceramic thin films, such as those used in coatings for high-performance cutting tools,” explain Erwin Peck and Balint Hadjas. “For high-performance tools, it’s essential that materials remain stable and durable under extreme conditions, and that’s exactly what makes these materials ideal for data storage as well.”
The researchers used a focused ion beam to engrave QR codes into thin ceramic layers. Each pixel is just 49 nanometers in size, about one-tenth the wavelength of visible light. As a result, the pattern is completely invisible under normal conditions and cannot be resolved using visible light. However, when viewed with an electron microscope, QR codes can be read clearly and reliably.
It also has excellent storage capacity. Using this approach, more than 2 terabytes of data fit within the space of a single A4 sheet of paper. Unlike traditional storage systems, these ceramic data carriers can remain intact indefinitely and require no energy to maintain the stored information.
A new approach to long-term data storage
“We live in the information age, and the storage of knowledge in the media has an incredibly short shelf life,” says Alexander Kirnbauer. Magnetic and electronic storage devices often lose data after just a few years, especially without continued power, cooling, and maintenance. In contrast, ancient civilizations carved their knowledge into stone, allowing them to survive for thousands of years.
“With ceramic storage media, we are pursuing an approach similar to ancient cultures, whose inscriptions can still be read today,” says Kirnbauer. “We write information into a stable, inert material that will stand the test of time and be fully accessible to future generations.”
Another big advantage is energy efficiency. Unlike modern data centers that require large amounts of power and cooling, ceramic-based storage can store information without continuous energy input, reducing environmental impact.
Guinness records and future applications
Its verification process, which included a documentary QR code and an electron microscope reading, was carried out jointly by TU Wien and Cerabyte in the presence of witnesses. The University of Vienna acted as an independent verification body. The Vienna University of Technology provided the USTEM Center with state-of-the-art materials science facilities along with high-resolution electron microscopy. This result was officially recognized by Guinness, with the new QR code being only 37% the size of the previous record holder.
“This world record is just the beginning of a very promising development,” says Alexander Kirnbauer. “We are now aiming to use other materials, increase write speeds, and develop scalable manufacturing processes so that ceramic data storage can be used not only in the laboratory but also in industrial applications. At the same time, we are investigating how more complex data structures, far beyond simple QR codes, can be robustly, quickly and energy-efficiently written into ceramic thin films and read out reliably.”
This work points to a more sustainable future for data storage, where information can be stored securely for long periods of time with minimal energy usage.
