Data storage

Major breakthrough for efficient, high-speed spintronic data storage devices

Ultra-fast magnetic scattering on ferrimagnetics powered by a soft Yb-based X-ray light source, which made the cover of Optica. Credit: Ella Maru Studio

Researchers from INRS and international partners have succeeded for the first time in studying the spin inside rare earth materials, using an ultrafast tabletop soft X-ray microscope.

Complex networks of systems are needed to share information in real time. Switching the magnetization, or electron spin, of magnetic materials with ultra-short femtosecond laser pulses is a promising strategy for accelerating data storage devices. However, how spin evolves in the nanoworld on extremely short timescales, like a millionth of a billionth of a second, has remained largely mysterious. In collaboration with TU Wien, Austria, the French national synchrotron center (SOLEIL) and other international partners, the team of Professor François Légaré at the National Institute for Scientific Research (INRS) has achieved a significant breakthrough in this domain. On April 6, 2022, their study was published in the journal Optical.

Until now, studies on the subject have largely relied on large, limited-access X-ray facilities such as free-electron lasers and synchrotrons. The team demonstrates, for the first time, a tabletop ultrafast soft X-ray microscope to spatiotemporally resolve spin dynamics inside rare-earth materials, which hold promise for spintronic devices.

This new soft X-ray source based on a high-energy Ytterbium laser represents a significant advance in the study of future high-energy, high-speed spintronic devices and could be used for many applications in physics, biology and chemistry.

“Our approach provides an elegant, robust, cost-effective, and energy-scalable solution for many labs. It enables the study of ultrafast dynamics in nanoscale and mesoscale structures with nanoscale and femtosecond temporal spatial resolutions, as well as with element specificity,” explains Prof. Andrius Baltuska, from TU Wien .

X-ray light pulses to observe rotation

With this bright source of X-ray photons, a series of snapshot images of nanoscale rare-earth magnetic structures were recorded. They clearly exhibit the rapid degaussing process and the results provide rich magnetic property information that is as accurate as that obtained using large-scale X-ray facilities.

“The development of ultrafast benchtop X-ray sources is exciting for advanced technology applications and modern scientific fields. We are excited about our results, which could be useful for future research in spintronics, as well as other potential fields,” says INRS postdoctoral researcher Dr. Guangyu Fan.

“Rare-earth systems are trending in the community due to their nanoscale size, faster speed, and topologically protected stability. The X-ray source is very interesting for many studies on future spintronic devices composed of rare earths. says Nicolas Jaouen, principal investigator at the French national synchrotron.

Professor Légaré emphasizes collaborative work between experts in the development of state-of-the-art light sources and ultrafast dynamics in magnetic materials at the nanoscale. “Given the rapid emergence of high-power ytterbium laser technology, this work represents enormous potential for high-performance soft X-ray sources. This new generation of lasers, which will soon be available at the Advanced Laser Light Source (ALLS), will have many future applications for the fields of physics, chemistry and even biology,” he says.

Reference: “Ultrafast magnetic scattering on ferrimagnets enabled by a bright Yb-based soft x-ray source” by G. Fan, K. Légaré, V. Cardin, X. Xie, R. Safaei, E. Kaksis, G. Andriukaitis, A. Pugžlys, BE Schmidt, JP Wolf, M. Hehn, G. Malinowski, B. Vodungbo, E. Jal, J. Lüning, N. Jaouen, G. Giovannetti, F. Calegari, Z. Tao, A. Baltuška, F. Légaré and T. Balčiūnas, April 6, 2022, Optical.
DOI: 10.1364/OPTICA.443440

The study received financial support from the Natural Sciences and Engineering Research Council of Canada, the Fonds de recherche du Québec – Nature et technologies (FRQNT) and PRIMA Québec, among others. The ALLS laboratory also benefits from an investment from the Canada Foundation for Innovation (CFI).

About INRS

INRS is a university dedicated exclusively to research and graduate training. Since its creation in 1969, INRS has played an active role in the economic, social and cultural development of Quebec and ranks first for the intensity of research in Quebec. INRS is made up of four interdisciplinary research and training centers in Quebec City, Montreal, Laval and Varennes, specializing in strategic sectors: Water Earth Environment, Energy Materials Telecommunications, Urbanization Culture Society and Armand-Frappier Health Biotechnology. The INRS community includes more than 1,500 students, postdoctoral fellows, faculty members and staff.