E-Mail IMAGE: His inventions in the field of spintronics have revolutionised computer technology. For this, Stuart Parkin will be honoured with the King Faisal Prize for Science 2021. view more Credit: Marco Warmuth, TGZ Halle GmbH Parkin's inventions in the field of spintronics have revolutionised computer technology, making it possible to increase the data density on hard disks by a factor of 1000. With his research on thin magnetic layers, he created the basis at IBM on which the company developed a new read head for hard disks. This reads data reliably even from very densely packed magnetic storage materials. This laid the foundation for Big Data, i.e. the handling of large amounts of data. Not least because of this, films and pictures can now be easily exchanged via social networks or computer clouds, making them available to groups of networked computers. These spin-valve recording read heads were only the tip of the spintronics iceberg. As a second major invention, more than 20 years ago at IBM, Parkin demonstrated a high performance, non-volatile magnetic random-access memory (MRAM), that became a mainstream foundry technology just last year. Recently, Parkin pushed the memory-storage capacity boundary further with the invention of the magnetic Racetrack Memory, whose fundamental principle is entirely different from the charge-based memories of today. Racetrack Memory stores information in the presence or absence of magnetic domain walls that are shifted backwards and forwards along nanoscopic magnetic racetracks, using spin currents. Over the past decade, Parkin demonstrated the fundamental concepts underlying his invention. A series of basic discoveries and key inventions in chiral spintronic materials and devices have proven that Racetrack Memory has great promise to displace today's storage devices, such as magnetic hard disk drive and solid-state FLASH memory.