Prize talk: APS Medal for Exceptional Achievement in ResearchSpintronics!

For 500 years we lived in an analogue world where information was stored and preserved on paper, in books and paintings and in videotapes. Today we live in a world that has become digital in just a short space of time, barely more than a decade ago. This was made possible by advances in computing power, communications, and, most importantly, by our ability to store all information digitally in the cloud, in magnetic disk drives. I will briefly introduce spin-based magnetic sensors – spin-valves – that made this technological revolution possible and discuss two other major spin-based digital memory storage technologies, magnetic random-access memory and magnetic racetrack memory. The former, proposed initially in 1995, became a mainstream foundry technology in 2019, and the latter is on the path towards replacing magnetic disk drives with a solid state device with no moving parts that is orders of magnitude faster and energy efficient. All three spintronic technologies, spin-valves, magnetic random-access memory and racetrack memory, are formed from exquisitely, atomically engineered magnetic heterostructures that can be mass produced. The properties of these devices are determined and/or manipulated by spin-polarized electrical currents or spin currents that are generated from charge currents via various intrinsic or extrinsic phenomena. In this talk I review the development of the field of spintronics, its impact and my own contributions over the past 3 decades.