Anglo-Japanese-Czech team uses abundant antiferromagnetics in tunnel junction.
A multinational team has developed the first spintronics device based on antiferromagnetic materials, potentially addressing the risk of increasing interference as structures and components are packed ever closer in components and tapping a much wider range of raw materials for use in electronics.
In an antiferromagnet, electron spin is ordered but that which is present in one group of atoms within a crystal will be matched by a group elsewhere that has the opposite orientation. As a result, these materials do not produce a magnetic field that could affect neighbouring elements. They also have the benefit of being extremely common – examples include chromium, iron manganese and nickel oxide.
The new device is a tunnel junction where one of the electrodes is an antiferromagnet and the other a non-magnet. When rotation of the spins in the antiferromagnetic electrode was induced, there was a large change in the tunnel resistance, comparable to that already seen in ferromagnetic spintronic research.
The work was carried out by scientists at Hitachi labs in the UK and Japan, in cooperation with colleagues at the Academy of Sciences and Charles University in the Czech Republic.
They say the observed behaviour is based on a “quantum-relativistic phenomenon” and describe the work in more detail in the latest issue of Nature Materials.