Abstract
The future of magnetic recording is a matter of considerable debate because it appears to be approaching various physical limits imposed by the dynamics of the recording process. In conventional magnetic recording, for example, information is recorded on a thin film containing a magnetic layer that is divided into small domains, each with a well defined magnetization. Information is "written" by reversing the direction of magnetization using an external magnetic field that is antiparallel to this direction. But this technique limits the "speed" of the recording process to the nanosecond level. Now Christian Back from the ETH in Zurich and co-workers in Switzerland and the US have used ultrafast magnetic-field pulses to reverse the magnetization of cobalt films in 2 picoseconds (Science 1999 285 864).