At a Glance
- For the first time, scientists have directly observed bulk magnons, also known as spin waves, at the nanoscale inside a nickel oxide nanocrystal using a novel method.
- The breakthrough was achieved by combining a high-energy-resolution scanning transmission electron microscope with two powerful theoretical and computational methods developed at Uppsala University called TACAW and UppASD.
- Magnons are crucial for the field of magnonics, which aims to use spin waves instead of electric charges to carry information, promising faster and more energy-efficient technology.
- Previously, it was nearly impossible to study how magnons behave around nanoscale defects, a critical step for understanding and designing functional spintronic devices for the future.
- This landmark discovery, published in Nature, opens up new avenues for exploring and controlling magnetism at the atomic level, thereby accelerating the development of next-generation spintronic and quantum technologies.
For the first time, scientists have directly observed elusive quantum waves, known as magnons, at the nanoscale inside a material, a breakthrough that could pave the way for a new generation of electronics. The international collaboration, detailed in a study published in the journal Nature, combined a state-of-the-art electron microscope with powerful computer simulations to visualize these tiny magnetic ripples, opening new avenues for controlling magnetism at its most fundamental level. This achievement helps overcome significant hurdles in developing technologies that are faster, smaller, and more energy-efficient than current systems.
The world of modern electronics is built on transistors, tiny switches that control the flow of electric charge. As these components shrink, they face fundamental limits related to heat and processing speed. To solve this, scientists are exploring spintronics, a field that uses an electron’s magnetic property, or “spin,” to carry information. This information travels in the form of synchronized waves of atomic spins, known as magnons. In magnetic materials, these magnons behave like a coordinated “dance” of countless tiny magnets, but observing them at the scale of individual atoms has been a monumental challenge until now.
To capture this quantum dance, researchers utilized a scanning transmission electron microscope (STEM) at the SuperSTEM laboratory in the UK, which is capable of resolving energy shifts as small as 7 millielectronvolts. As a high-energy electron beam passed through a nickel oxide nanocrystal, it lost minuscule amounts of energy, leaving a faint signature of the magnons within. To decipher these signals, a team at Uppsala University in Sweden developed two key theoretical methods. The first, called TACAW, simulated the interaction between the electrons and magnons, while the second, a software known as UppASD, modeled the behavior of the magnons themselves.
“We could suddenly see all the magnons and every step of their dance at the nanoscale,” said José Ángel Castellanos-Reyes, a researcher at Uppsala University and co-first author of the study, in a university press release. This newfound ability to observe how magnons behave around nanoscale features, such as impurities or missing atoms, is crucial for ensuring the quality control of future devices. The discovery marks a significant milestone in the field of magnonics, promising to accelerate the design of advanced spintronic technologies that could redefine computing and data transfer.
References
- Kepaptsoglou, D., Castellanos-Reyes, J. Á., Kerrigan, A., Alves Do Nascimento, J., Zeiger, P. M., El Hajraoui, K., Idrobo, J. C., Mendis, B. G., Bergman, A., Lazarov, V. K., Rusz, J., & Ramasse, Q. M. (2025). Magnon spectroscopy in the electron microscope. Nature. https://doi.org/10.1038/s41586-025-09318-y
- Uppsala University. (2025, July 24). Spin waves observed directly at nanoscale for first time. Phys.Org; Uppsala University. https://phys.org/news/2025-07-nanoscale.html
