In addition to enhancing our understanding of the spin of electrons, this makes it possible in the long term to construct much faster, smaller and more economical magnetic memories. The research was published on 29 September on the website of the renowned journal Nature Physics.

The physicists carried out the experiments in a home-built nano-playground, which is an ideal environment for the experiments. This environment consisted of two nano-reservoirs, with an intermediate thin layer of conductive or insulating material. By focusing an ultrashort laser pulse (ca. 100 femtoseconds, 10-13 seconds) on one reservoir, a number of electrons proved to travel to the other reservoir while their spin was maintained. As a result, the bit was switched.

Such fast movement of electron spin (spin transfer) means that it will become possible to switch magnetic areas on these extremely short time scales. In the long run this can make magnetic memories faster by orders of magnitude.

According to Koopmans the researchers in this research are joining two developments: the ultrafast manipulation of bits, and the writing of this information onto minute structures. This brings two important properties for electronics together: faster and smaller. Faster, for a switching time of 100 femtoseconds makes it possible theoretically to achieve a writing speed of terabits per second. And smaller, for the use of ‘spin transfer’ makes smaller MRAM-memories (Magnetoresistive Random Access Memory) possible. This breakthrough opens the way to better experiments in this direction.

The researchers expect that within one or two years the first MRAM-memories based on spin transfer will appear on the market. MRAM is a low-energy type of computer memory that is permanent and does not require any starting time. For over two years now the first MRAM-memories have been on the market. However, at present these still work many thousands of times more slowly than the system built by the researchers of Physics of Nanostructures. Koopmans: “You should still look upon this as fundamental physics, it is a ‘proof of principle’, but the next step will be closer to a solution.”/.

The publication ‘Control of speed and efficiency of ultrafast demagnetization can be found on: www.nature.com/ nphys/journal/vaop/ncurrent/ pdf/nphys1092.pdf.