Next-Generation Nanotechnology

Spintronic devices will make technology faster, smaller, and smarter


Spintronic materials are the Holy Grail of nanotechnology. They have the potential to dramatically reduce the size of devices and improve their efficiency, creating the next generation of fast, powerful, and miniaturised technology. But we’re not there yet. Scientists around the world are currently on the hunt for these special materials, looking for ways to make them usable in real-life conditions. At Diamond, scientists are joining the search for a perfect spintronic material with research that will help to shape the future of technology.
Moore’s Law observes that the amount of processing power required by technology doubles about every two years. In the 1970s, a computer would have about 20,000 ‘transistors’ – tiny devices that help to transfer data. These days, an iPhone 6 has two billion.
We’re requiring more and more nanotech components to create our advanced devices, but we have a problem: more components require more space and more power. So we have two options: we can either reduce the size of these components, or we can make them more efficient.
In the past, we’ve been focussed on trying to bring down the size of technology components, but we’ve almost reached the limit for how small we can get them. And so fairly soon, we can expect to see devices getting bigger and hotter, as they eat up more energy to keep running. That’s why scientists are looking to create transistors from new materials that use less power and transfer data more efficiently, allowing us to pack the same computing power into ever smaller devices.
Normal transistors work like tiny electronic switches. They transfer data and essentially enable all action to take place on devices: from opening up an app to making a call. But for transistors to work, they need to be exposed to a voltage.
If we can make these transistors out of a different class of materials – known as spintronic materials – it’s possible to make them much more efficient. Instead of transferring information using electron charge, like regular transistors do, spintronic transistors could exploit another fundamental property of electrons: their spin. This would allow us to transfer data, not through charge, but by the flow of electrons with a specific spin, thus making spin-based transistors much more powerful than traditional ones.
Diamond's angle-resolved photoemission spectroscopy beamline (I05)
Spintronics could allow future electronic devices to be faster and use less power without becoming bigger. We wouldn’t need larger processors and massive batteries to get the same computing power and battery life out of laptops and mobile phones. We could also create devices that run for weeks or months on a single charge – no more having to plug in your phone every other day. With spintronic technology, the possibilities really are limitless, and learning how to exploit their potential could bring us into a new age of advanced computing power.
But to create transistors capable of this feat, we need to find the perfect material that can control electronic spin and also function in a real-life setting, at normal temperatures and pressures. Prototypes do exist, but this is a burgeoning field and no clear solution has yet been found. So scientists at Diamond are joining efforts to find this precious material and learn how to manipulate it.
Jonathon Riley is a joint PhD student between Diamond and the University of St Andrews. He’s using Diamond’s angle-resolved photoemission spectroscopy beamline, I05, to study spintronic materials. Here, Jonathon can probe these materials and investigate how electrons move around inside.
One of the samples Jonathon is studying is called tungsten diselenide, and it shows promise as a potential spintronic material. Using photoelectric techniques Jonathon shines X-rays generated by the synchrotron onto the tungsten diselenide samples, causing electrons to eject from the surface of the material. The ejected electrons retain a lot of their information and, by studying them, Jonathon can work out the complex pattern of how they were moving and the energies they had when they were inside the material. 
Jonathon can also manipulate the electronic environment of the tungsten diselenide and record how the electron behaviour changes. In this way, he’s able to find out more about the material and how it could be exploited for use in a spin-transistor.
But that’s not all: in the future, Jonathon will scrutinise the behaviour of this material and others like it under different temperatures and chemical environments to ensure that it is workable under real-life conditions. With a deep understanding of how these materials behave, we will be in a better position to build a fully functioning spin-transistor.
Jonathon’s research is part of a wider movement around the world to track down potential spintronic materials and, as Jonathon observes, this is very much a communal effort: “Scientists everywhere are really excited about the potential of spintronics, so it’s little wonder that many groups are working on developing them. All this research is building up our understanding of these remarkable materials and bringing the age of spintronic technology closer.” He continues: “You never know when these things are going to happen, but new scientists are always joining the hunt. There’s no doubt in my mind that we’ll find the right material eventually.”
Spintronics have the potential to revolutionise technology and completely redefine what devices can do. These materials are highly complex and making them usable will require more research and understanding. But every day science is bringing us closer to harnessing the power of spintronics and, with the combined efforts of bright minds around the world, finding that perfect substance is just a matter of time.