Magnetic materials could now be developed faster than ever before, thanks to computer modelling techniques used to build two new types of magnets, atom-by-atom.
With only about 5 percent of known inorganic compounds showing even a hint of magnetism, scientists are keen to develop new materials in the lab to supplement them.
This research focussed on a family of materials called Heusler alloy, composed of atoms from three different elements arranged in one of three distinct structures – giving 236,115 possible combinations in all.
By using computer models of potential prototypes – which calculated how atoms might interact, and the energy that would be required – the list was quickly cut down.
Finally, scientists were left with 14 candidates for new materials that they could then work on synthesising in the lab: of four that were chosen, two were eventually developed over the course of several years.
Although the synthesising process is still relatively slow, working on a handful of potential compounds is easier than trying to find the right combination in a group of 236,115, which is why the computer modelling technique could be so useful.
The first new material, #Co2MnTi, consists of cobalt, manganese, and titanium, and researchers were able to accurately predict the new magnet’s properties, including the Curie temperature (the point when the material loses its magnetism).
That temperature turned out to be 938 Kelvin (1,228 degrees Fahrenheit), very close to the predicted 940 Kelvin (1,232 degrees Fahrenheit), making the material potentially useful in many commercial applications.
The second magnetic material, #Mn2PtPd, mixes manganese, platinum, and palladium, and although it doesn’t actually produce a magnetic field of its own, it has electrons that react strongly to magnetic fields. This would make it a good candidate for use in hard drives although, beyond that, its use is somewhat limited because its behavior is difficult to predict.
Mn2PtPd was found to be an antiferromagnet, where electrons are evenly divided in their alignments – meaning the material has no internal magnetic moment of its own, but its electrons are responsive to external magnetic fields.
This material could be used in hard drives, Random Access Memory (RAM), and magnetic field sensing devices, the scientists say, but the method used to find these materials is what’s most important.