An Irish breakthrough in the big data storage problem

The world is sinking under a flood of data. Information rolls in from all directions, to be saved in huge data centres where storage discs spin 24-7. People are plugging all sorts of devices into the internet and saving the raw data coming from them.

This “internet of things” is adding an estimated 5.5 million devices a year to the net, and by 2020 there will be almost 21 billion wirelessly connected devices online.

But what are we going to do when the storage space runs out?

All this data is stored using technology based on magnets, so the answer to the problem must lie in developing new kinds of magnets that can store more data and collect and share it at much higher speeds.

Researchers at Trinity College Dublin believe they have done just that with an announcement this morning about a "breakthrough" that provides an answer to the two big problems relating to data centres: storage density and data transfer rates. The goal is to be able to pack more information into a smaller space and move that data into and out of the data centre at much higher speeds.

The discovery comes from Trinity's Amber nanotechnology research centre and has the potential to change the way we store data. The device under development can transfer data 100 times faster than the current best hard-drive storage and it packs more information into a smaller space.

Magnetic personality

One of the leading researchers behind the work is a world expert in magnetism and magnetic materials, Prof Michael Coey, who is a principal investigator at the Amber centre. "I have studied magnetism for 50 years and I love it," he says. "It keeps coming up as a subject, and there is always something new."

His involvement in the study of magnetism came about almost by accident. “I have worked all my life in magnetism and . . . I got into it when I was 21 and working in a school in India as a teacher,” he says.

He took ill and was told to take a month off, so he travelled around the country on trains. He decided to use the long, slow journeys to decide on a PhD topic. He had with him a copy of The Physical Principles of Magnetism, considered the essential text for understanding magnetic materials, and read it through in one go.

“And that was it. I have worked in magnetism ever since,” he says.

The discovery brings data storage to a new level. The device would use individual electrons as memory units so vast amounts of data could be held in a very small space.

The idea is based on each electron acting like a tiny permanent magnet. “Conventional electronics forgot the electron was a magnet,” he says. “It was only when people started looking at magnetic-field effects on electrical conductivity that they began to take account of an electron being a tiny magnet.”

Their advance uses an effect called "spin-orbit torque", but is based on the use of their new magnetic material. "We found a new material that doesn't produce a magnetic field but behaves inside like a ferromagnetic material," he says.

The team includes experts in magnetism and magnetic switching – which lie at the heart of data storage – who developed a stack of five metal layers, each of them just a few nanometres thick. A nanometre is a billionth of metre.

Only the lower layer stores data, but it does so at very high densities. It also allows high-speed switching that is 100 times faster than current systems.

“We believe we can make a chip-to-chip transmitter receiver so data rates rise, and we will remove one of the roadblocks,” says Prof Coey who is a Fellow of the Royal Society and holds a Royal Irish Academy Gold Medal for his research.

"These are ideas, hopes, possibilities, but [we are] not yet there," he says. Details of their work were published this month in the journal Nature Nanotechnology.

The team plans to demonstrate a full memory cell based on the approach, using their new magnetic alloy. The scales are so small that the stacks will have to be grown rather than built, using a new device installed at Amber with funding from Science Foundation Ireland.

Their device needs far less electricity to operate, so the cost of running huge data centres would be reduced. It would also mean there would be less waste heat coming from them. And more data could be packed away in a given space compared with today’s hard drives, they say.

The device has the potential to sustain the information revolution for another 25 years, the research team believes.

ZERO-POINT ENERGY: NOT-SO-EMPTY SPACE
Strange things can arise when you study magnetism, such as proving there is free energy available in totally empty space.

Trinity College Dublin’s Prof Michael Coey and colleagues were “astonished” when they detected an extremely weak but persistent magnetic field in something that shouldn’t be magnetic at all.

Theoretical physicists have long believed that empty space is not really empty at all, but filled with leftover “zero-point” energy, the residue left behind by passing electromagnetic radiation.

This includes light, radio waves, and x-rays, and the theory holds that the radiation leaves energy in its wake when passing through empty space.

The fact that the energy is there in minute amounts was shown by separate scientists working in the US and the Netherlands about 70 years ago, but no one had found other ways of seeing it until now.

The scientists at Trinity were working with cerium dioxide nanoparticles, a material used in car exhaust systems. Unexpectedly, they detected a strange magnetic effect in the material and decided to study it.

They found the effect was there when the cerium dioxide was clumped together but it disappeared when the material was spread out.

They tried it with ordinary sugar and found a magnetic field if the sugar crystals were clumped, but no field if the sugar was dissolved. The magnetism would return, however, if the sugar was recrystallised out of the water.

The team concluded – in the journal Nature Physics – that the magnetism formed in the clumps because of the surrounding zero-point energy. Unfortunately the scientists have yet to discover a way to tap into this free energy source.