Abstract

Spintronics is a field of research that harnesses the electron’s spin to create novel materials with exotic properties and devices especially those for storing digital data that is the lifeblood of many of the most valuable companies today. Spintronics has already had two major technological successes with the invention and application of spin-valve magnetic field sensors that allowed for more than a thousand-fold increase in the storage capacity of magnetic disk drives that store ~70% of all digital data today. Just recently, after almost a 25-year exploration and development period, a high performance nonvolatile Magnetic Random Access Memory, that uses magnetic tunnel junction memory elements, became commercially available. A novel spintronics memory-storage technology, Magnetic Racetrack Memory is on track to become the third major success of spintronics. Racetrack Memory is a non-volatile memory in which data is encoded in mobile chiral domain walls that are moved at high speeds by spin currents to and thro along synthetic antiferromagnetic racetracks1-3.

In this lecture I will discuss the developments of spintronics over the past 35 years and its future potential and prospects for both conventional memory-storage as well as for cryogenic racetrack memory technologies to support cryogenic quantum computing systems.

1: Parkin, S. S. P., Hayashi, M. & Thomas, L. Magnetic Domain-Wall Racetrack Memory. Science 320, 190-194 (2008). https://doi.org/10.1126/science.1145799 2: Jeon, J.-C., Migliorini, A., Yoon, J., Jeong, J. & Parkin, S. S. P. Multi-core memristor from electrically readable nanoscopic racetracks. Science 386, 315-322 (2024). https://doi.org/10.1126/science.adh3419 3: Farinha, A. M. A., Yang, S.-H., Yoon, J., Pal, B. & Parkin, S. S. P. Interplay of geometrical and spin chiralities in 3D twisted magnetic ribbons. Nature 639, 67–72 (2025). https://doi.org/10.1038/s41586-024-08582-8