Researchers target new form of RAM from rare materials

Researchers from Victoria University, in New Zealand, are studying the application of a class of materials called rare earth nitrides (RENs) to create a new type of non-volatile RAM memory.

Dr Ben Ruck, Professor Joe Trodahl and Dr Franck Natali from the School of Chemical and Physical Sciences, are studying potential commercial applications of RENs, thin films grown under ultra-high vacuum which are both magnetic and semiconducting.

Two concepts already patented include developing the first magnetic memory storage devices based on RENs, called "magnetic tunnel junctions".

The issue with current forms of RAM is that it does not retain information when the host computer is turned off, says Ruck.

“What we’re working on is a magnetic type of RAM that doesn’t disappear. Because data is retained when the power is switched off, a device can perform faster, be more versatile and use less energy. This is ideal, as an example, for cloud data storage spanning across multiple servers,” he says.

The new materials may be useful in developing this magnetic RAM, or MRAM, that uses electron spin, not charge, to store data.

The team has worked with europium nitride, for instance, which is not usually magnetic, but has been "tricked" into behaving like a magnet by being produced with slightly too few nitrogen atoms.

The Victoria team is collaborating with a researchers at the Centre for Research on Hetero-Epitaxy and Applications, in France, which has facilities to grow pure versions of RENs.

Ruck and his colleagues are also in the process of testing a new way to control how RENs use electricity. 

“No one has made a magnetic semi-conductor where you can truly control the electrical conductivity,"Ruck says. "Our results provide a new way to control conduction precisely, meaning you can swap a device from being magnetic to non-magnetic, surpassing existing electronics regarding speed and power consumption.”

This would be a significant breakthrough for developing and constructing spintronics devices, an emerging technology where the spin of an electron is controlled to manipulate its charge.