A new material, which can be useful in developing highly energy-efficient IT applications, has been developed by an international research group in collaboration with Martin Luther University Halle-Wittenberg (MLU).
The unique properties of the electrons located at the material’s oxide interface dramatically increase the rate of conversion of spin current into charge current. This is the basis for next-generation spintronic applications. The researchers have reported in the Nature Materials journal that they have found the new material to be more efficient compared to any material investigated earlier.
Electric current flows through all technical devices, as a result, heat is produced and energy is lost. Spintronics investigates new strategies to overcome this problem that involves using a unique property of electrons—spin. This is a kind of intrinsic angular momentum of electrons that produces a magnetic torque. This is what gives rise to magnetism.
The concept behind spintronics is as follows: If spin current flows through a material rather than electrical charge, heat is not generated and considerably less energy is lost in the device.
However, this approach still requires an electric current for the device to work. Therefore, an efficient spin-to-charge conversion is necessary for this novel technology to work.
Ingrid Mertig, Physicist and Professor, Martin Luther University Halle-Wittenberg
Her research team is part of the international research group that found out the new material. The study was headed by the French physicist Dr Manuel Bibes, who performs studies at the well-known institute Centre national de la recherche scientifique (CNRS)–Thales.
The team analyzed the interface between two oxides.
The two substances are actually insulators and are non-conductive. However, a kind of two-dimensional electron gas forms at their interface, which behaves like a metal, conducts current and can convert charge current into spin current with extremely high efficiency.
Two members of her research team, Dr Annika Johansson and Börge Göbel, offered the theoretical interpretation for this strange observation. The researchers said that the new material is much more efficient compared to any other known material. This could open the door to developing new, energy-saving computers.
MLU has wide proficiency in the area of oxide interfaces. From 2008, Collaborative Research Centre 762 “Functionality of Oxidic Interfaces” has been sited at MLU, funded by the Deutsche Forschungsgemeinschaft (German Research Foundation, DFG). The CRC is part of the university’s core research area “Materials Science–Nanostructured Materials.”
The concept for the project emerged during Manuel Bibes’ guest stay in Halle last year. Bibes was awarded the Alexander von Humboldt Foundation’s Friedrich Wilhelm Bessel Research Award. The award is given to internationally renowned researchers from abroad for their research accomplishments. Scientists can use the prize money for research stays at German research institutions and universities.