Buckyballs research paves way for next gen spintronics devices
2 mins read
In a bid to find a material that combines the characteristics of a semiconductor - such as silicon - with magnetic properties, a spintronics researcher believes he may have found the answer.
Michel de Jong from Twente University is focusing on semiconductors consisting of carbohydrate chains – organic materials.
Spintronics has the potential to be very fast and extremely compact. An electron's spin responds rapidly to small magnetic fields. Such external magnetic fields can be used to reverse the direction of spin, so information can be carried by a flow of electrons. For example, electrons with a left hand spin could represent a '1' and those with a right hand spin, a '0'. It takes less time to flip the spin direction than it does to switch a current on or off. To achieve this requires a material such as the carbohydrate chains researched by de Jong.
"Such materials are already being used in the displays of the latest smartphones," said de Jong. "Indeed, they are very much the 'in thing'. I expect it will ultimately be possible to make very cheap electronics from these materials, leading to a wide range of new applications. For instance, if supermarkets want to tag their products with pricing information, then the electronics involved will have to cost next to nothing."
De Jong has been experimenting with spherical C60 molecules held together by weak bonds, called buckyballs. The buckyballs are sandwiched between two magnetic materials and, according to de Jong, have very little effect on the electron spin: "This enables them to store spin information for much longer periods of time than silicon." Depending on the orientation of the magnetic field in the upper and lower layers of magnetic material, electrons with the same direction of spin are either allowed through or held back, as if a valve were being opened or closed. This, says de Jong, would make it possible to create sensitive magnetic sensors for example. In theory, the 'sandwich' could also form the basis for new electronic components that make use of spin.
"If we are to make truly effective components, we will need a detailed understanding of events at the interface between the magnetic and organic materials," de Jong added. "However, this will require improvements in the quality of such interfaces. The current techniques for applying metallic layers to organic layers do not produce good interconnections. The organic material contains cavities that can fill with metal. This results in unpredictable behaviour. Over the next five years we will be seeking to improve the manufacturing process. This will help us to understand what exactly happens at the interface. I propose to use part of the ERC Grant for this purpose. It will enable me to take on two PhD students and a postdoctoral researcher."
This is the second major ERC Grant to be awarded to Prof Wilfred van der Wiel's group NanoElectronics, part of the MESA+ Institute for Nanotechnology of the University of Twente.
