All-optical switching promises terahertz-speed hard drive
and RAM memory
Researchers at the U.S. Department of Energy’s Ames
Laboratory, Iowa State University, and the University of Crete in Greece have
found a new way to switch magnetism that is at least 1000 times faster than
currently used in magnetic memory technologies. Magnetic switching is used to
encode information in hard drives, magnetic random access memory and other
computing devices. The discovery, reported in the April 4 issue of Nature,
potentially opens the door to terahertz (1012 hertz) and faster memory speeds.
Ames Laboratory physicist Jigang Wang and his team used
short laser pulses to create ultra-fast changes in the magnetic structure,
within quadrillionths of a second (femtosecond), from anti-ferromagnetic to
ferromagnetic ordering in colossal magnetoresistive materials, which are
promising for use in next-generation memory and logic devices. Scientists, led
by Ilias E. Perakis, at the University of Crete developed the theory to explain
the observation.