Researchers from RMIT and the University of New South Wales, (UNSW) have discovered magnetic properties within atomically thin structures that could be used for a new generation of devices, known as “spintronics”.
With further research in this field, ultra-thin devices could be produced for industrial applications.
This research created devices with three layers, a non-magnetic graphite in the middle and two ferromagnetic materials on the outside. The outside layers are two-dimensional materials, known as Fe3GeTe2 (FGT) and the entire three-layer devices are known as van-der-Waals (vdW) hetero-structures.
The research is in the field of “spintronics”, devices in which use a quantum property known as “spin” that occurs in addition to electronic charges in conventional electronics.
While still in its experimental phase, this research demonstrates that “spintronics” could provide functional devices.
According to study co-author Sultan Albarakati, the researchers were able to uncover a mode of giant magnetoresistance (GMR), previously entirely unknown.
“This reveals that vdW ferromagnetic hetero-structures exhibit substantially different properties from similar structures,” said Albarakati.
GMR is commonly used for magnetic recording, and its two states, high and low resistance are widely known. In this research, the team from RMIT and UNSW found a third, intermediate resistance state.
According to co-author Cheng Tan, this finding will open up areas otherwise thought settled.
“This work has significant interest for researchers in 2D materials, spintronics, and magnetism. It means that ‘traditional’ tunnelling magnetoresistance devices, spin-orbit torque devices and spin transistors may reward being re-investigated using similar vdW hetero-structures to reveal similarly surprising characteristics,” said Tan.
The researchers from the two universities collaborated through UNSW’s Centre for Future Low-Energy Electronics Technologies (FLEET). FLEET seeks to develop ultra-low energy electronics which can reduce energy use in computation.
Researchers were assisted by colleagues from the South China University of Technology and the Chinese Academy of Sciences.