New holographic memory device could improve storage capacity and processing

A new holographic memory device can provide unprecedented data storage capacity and data processing capabilities in electronic devices like computer, pen drive or cell phone.

This memory device uses 'spin waves' - a collective oscillation of spins in magnetic materials - instead of optical beams.

Spin waves are advantageous because spin wave devices are compatible with the conventional electronic devices and may operate at a much shorter wavelength than optical devices, allowing for smaller electronic devices that have greater storage capacity.

"The results open a new field of research which may have tremendous impact on the development of new logic and memory devices," said Alexander Khitun, lead researcher at University of California, Riverside.

The study found it was feasible to apply holographic techniques developed in optics to magnetic structures to create a magnonic holographic memory device.

Holography is a technique-based on the wave nature of light which allows the use of wave interference between the object beam and the coherent background.

It is commonly associated with images being made from light, such as on driver's licenses or paper currency. However, this is only a narrow field of holography.

Khitun and his team conducted the experiments using a 2-bit magnonic holographic memory prototype device. A pair of magnets, which represent the memory elements, were aligned in different positions on the magnetic waveguides.

Spin waves propagating through the waveguides are affected by the magnetic field produced by the magnets. When spin waves interference was applied in the experiments, a clear picture was produced and the researchers could recognise the magnetic states of the magnets. The findings of the study are published (advance copy) in the journal Applied Physics Letters.

There are three co-authors of the 'Magnonic Holographic Memory' paper: Frederick Gertz, a graduate student who works with Khitun at UC Riverside, and A. Kozhevnikov and Y. Filimonov, both of the Russian Academy of Sciences.