Researchers Measure Nanomagnet Attempt Time for First Time Since 1950s Overturning Decades of Theoretical Assumptions

Researchers at Tohoku University measure nanomagnet "attempt time" for the first time, finding it is 10x slower than the 70-year-old theoretical assumption.

By: AXL Media

Published: Apr 22, 2026, 4:30 AM EDT

Source: Information for this report was sourced from EurekAlert!

Redefining the Fundamental Stability of Magnetic Storage

The stability of digital information in hard drives and memory devices relies on the ability of microscopic magnets to maintain a consistent direction of magnetization. For nearly seven decades, the scientific community has operated under the assumption that these nanomagnets attempt to flip their magnetic orientation approximately once every nanosecond. However, new research from Tohoku University has finally put this long-standing theory to the test. By successfully measuring this "attempt time" experimentally for the first time, researchers have discovered that these fundamental shifts occur much more slowly than previously estimated, challenging the core physics used to design modern storage technologies.

The Role of Energy Landscapes in Thermally Activated Switching

To understand why magnets flip, researchers utilize the concept of an energy landscape, where two stable states of magnetization are separated by a physical energy barrier. Thermal fluctuations—essentially heat energy—can occasionally provide enough of a push to force the magnetization over this barrier, causing a bit of data to flip from a "north" to a "south" orientation. As technology advances and storage components become smaller, this energy barrier naturally lowers, making the data more vulnerable to heat-induced corruption. This relationship is governed by the Arrhenius law, which identifies the characteristic "attempt time" as the frequency at which the magnet tries to cross that barrier.

Experimental Breakthrough in Measuring Stochastic Behavior

The team, led by Associate Professor Shun Kanai, fabricated specialized nanomagnet devices and utilized scanning electron microscopy to precisely characterize their geometry. Unlike previous attempts that struggled to isolate the attempt time, the Tohoku researchers developed a unique analytical approach that allowed them to test the Arrhenius law at room temperature without the need to fluctuate the thermal environment. By observing how the magnets switched between opposite states under controlled conditions, they were able to extract the actual time constant associated with these stochastic attempts, providing the first empirical data for a value that had been a placeholder in physics equations since the mid-20th century.