Phys. Rev. Lett. 103, 117201 (2009)

The speed at which information can be recorded on a magnetic disc is limited by the time it takes to 'flip' the magnetic bits on the surface. Like a spinning top, these bits have momentum, and it takes them time to reverse their magnetism from one orientation to another using traditional means.

Now Kadir Vahaplar of Radboud University Nijmegen in the Netherlands, and his colleagues have found a faster way to flip the bits. The team used a powerful pulse of laser light to temporarily destroy and reorient the bits. A second pulse allowed them to read back the data. The entire process took just 30 picoseconds — ten times faster than today's technology.