Researchers from Cornell University in the US have built a memory device that encodes data at room temperature with nothing but an electric field.
While that may sound a little abstract, it opens up the potential for engineers to create instant-start computers that use far less energy than today’s models.
Right now, our computers store data using electric currents. This works pretty well, but it significantly limits how small we can make computers - the wires that carry a current can only get so tiny.
It also means that our computers use a lot of power and take a while to boot up when we switch them on. When you think about it, despite all the advances in technology, computers don't load up much faster now than they did 10 years ago.
The ideal solution would be for data to be encoded without current, for example, using an electric field applied across an insulator. This would use up much less energy and would allow computers to get much faster and smaller, and it’s something scientists have been struggling with for decades.
But now the team at Cornell have made a major breakthrough, by creating a room-temperature magnetoelectric memory device that is the equivalent to one computer bit.
Although it’s pretty small for now, this device is being called the “holy grail of next-generation nonvolatile memory”, and it can switch on (a process known as “magnetic switchability”) in two steps with nothing but an electric field.
"The advantage here is low energy consumption," said lead researcher John Heron, in a press release.
"It requires a low voltage, without current, to switch it. Devices that use currents consume more energy and dissipate a significant amount of that energy in the form of heat. That is what's heating up your computer and draining your batteries."
The device is made out of a compound called bismuth ferrite, which has a very rare trait - it’s multiferroic. This means it’s both physically magnetic (like a fridge magnet) and also ferroelectric, which means it’s always electrically polarised and creates a magnetic field. And that ferroelectric magnetic field can be switched using an electric field, which means it can be used to store data.
The best part is that it also works at room temperature. Previously, researchers have been able to achieve similar results with different materials, but only at crazily cold temperatures, such as 4 Kelvin (-269 degrees Celsius). This meant that they were never viable for being scaled up and used in people’s houses and industry.
"The physics has been exciting, but the practicality has been absent," said Darrell Schlom, the co-researcher on the project, in the release.
The discovery came after the team first theorised and then experimentally realised the kinetics of the switching in the bismuth ferrite device.
It had previously been predicted that the switching would happen in just one step, which means it can’t be used for a memory device. But they have now figured out that the switching occurs in two steps, proving that the material could have huge potential to revolutionise computing.
The device also seems to require an order of magnitude lower energy than other models out there.
But the researchers have a long way to go still - right now they only have the equivalent of one computer bit, and real-life computer memory requires billions of arrays of these devices. They also need to work on improving its durability.
But right now even the proof of concept is pretty exciting, and if we could use this material to create computers that load up instantly, that would be awesome.
Although the big question is… who even turns their computers off anymore?