The ability to record and store information at ultrafast speeds while generating only a tiny amount of heat is described in a paper published this week in Nature. The study may open up new opportunities for using light and magnetism to create next-generation information storage devices.

Magnetic materials, such as those in hard-disk drives, have long been used to read and write information. This has traditionally been an energy-intensive, relatively slow process that generates heat that subsequently needs to be removed.

Andrzej Stupakiewicz and colleagues now report a technique that uses a precisely tuned laser pulse to write magnetic units of information (bits) at room temperature. The authors note that this approach produces much less heat (less than six joules per cubic centimetre) than today’s hard-disk drives or flash memory. The recording event is also extremely fast, requiring fewer than 20 picoseconds (one picosecond is one-trillionth of a second) to complete. They suggest that their work could inform the design and development of future photo-magnetic recording technology.