Researchers develop new type of ‘ratchet memory’

A new type of memory that was developed by researchers from Eindhoven University of Technology and research institute FOM should be more economical and faster than current memory techniques, and last longer.

The memory could last a lot longer than the magnetic domains that are used in hard disks. The new memory also has a magnetic basis, but this is realized with nanowires. Magnetic domains are created in the round nanowires, and the researchers have developed a technique for storing data in those domains. This technique allowed the magnetic domains to get different magnetic directions from each other, instead of all pointing in the same direction.

By bombarding the nanowires with ion radiation, the researchers created an asymmetrical energy distribution in the nanowires, which acts as a ‘sawtooth’. The domain walls of the magnetic bits moving through the nanowires are kept separated by this sawtooth-shaped energy, while still being able to move. The bits are moved in the nanowires by an alternating magnetic field.

Due to the sawtooth-shaped potential differences in the nanowires, the new type of memory is called ratchet. With each change of the magnetic field, the magnetic domains are forced a notch further, where they cannot go back. The researchers want to further develop memory, but it will probably take years before it can be applied.