Depending on whether this voltage was positive or negative, the scientists could figure out if the antiferromagnets were coded as 1 or 0. This then allows the data stored in the materials to be read. "Our discovery provides a straightforward way to read data stored in antiferromagnets by being able to distinguish the two states the materials can take," said Assoc Prof Gao. "The findings advance research in using antiferromagnets for computer memory in the future." Chips for computer memory, also called random-access memory (RAM), are used to quickly access data, such as for opening software and editing documents in computers. Memory chips made with antiferromagnets are expected to store and change data more quickly than those made from magnetic materials called ferromagnets because they can change between the 1 and 0 states about 100 times faster. This is useful for resource-intensive computing tasks. Researchers from Israel's Weizmann Institute of Science, Japan's National Institute for Materials Science and China's Chongqing University also contributed to the NTU-led study. The research findings exemplify a key focus of the NTU 2025 strategic plan on interdisciplinary research with significant intellectual and societal impact.

 Scientists led by Nanyang Technological University, Singapore (NTU Singapore) investigators have made a significant advance in developing alternative materials for the high-speed memory chips that let computers access information quickly and that bypass the limitations of existing materials.

They have discovered a way that allows them to make sense of previously hard-to-read data stored in these alternative materials, known as antiferromagnets.

Researchers consider antiferromagnets to be attractive materials for making computer memory chips because they are potentially more energy efficient than traditional ones made of silicon. Memory chips made of antiferromagnets are not subject to the size and speed constraints nor corruption issues that are inherent to chips made with certain magnetic materials.

Computer data is stored as code comprising a string of 1s and 0s. Currently, methods exist to "write" data onto antiferromagnets, by configuring them so that they can represent either the number 1 or 0.

However, "reading" this data from antiferromagnets has proved elusive to researchers as there were no practical methods in the past that could figure out which number the materials were coded as.

Now scientists led by Associate Professor Gao Weibo from NTU's School of Physical and Mathematical Sciences (SPMS) have found a solution.

Results from their experiments, published online in the scientific journal Nature in June 2023, showed that at ultra-low temperatures close to the coldness of outer space, if they passed a current through antiferromagnets, a unique voltage was measured across them.