Researchers achieve magnetic lead-free halide double perovskites

Researchers at Linköping University in Sweden have announced the development of an optoelectronic magnetic double perovskite. The discovery could open the door to combining spintronics with optoelectronics for rapid and energy-efficient information storage.

The team explains that one type of perovskite that contains halogens and lead has recently been shown to have interesting magnetic properties, opening the possibility of using it in spintronics. Spintronics is thought to have huge potential for the next generation of information technology, since information can be transmitted at higher speeds and with low energy consumption. However, magnetic properties of halide perovskites have until now been associated only with lead-containing perovskites, which has limited the development of the material for both health and environmental reasons.

The scientists at Linköping University have now, together with a large group of colleagues in Sweden, the Czech Republic, Japan, Australia, China and the US, and led by Professor Feng Gao of LiU, managed to create lead-free perovskite alloy, and produce a magnetic double perovskite.

They show in their study that magnetic iron ions, Fe3+, are incorporated into a previously known double perovskite with interesting optoelectronic properties and consisting of cesium, silver, bismuth and bromine, Cs2AgBiBr6.

The researchers have shown in experiments that the new material has a magnetic response at temperatures below 30 K (-243.15 °C).

"These are preliminary experiments from an exploratory investigation, and we are not completely sure of the origin of the magnetic response. Our results, however, suggest that it is probably due to a weak ferromagnetic or anti-ferromagnetic response. If so, we have a whole class of new materials for future information technology. But more research is needed, not least to obtain the magnetic properties at higher temperatures," says Feng Gao.

"Perovskites are exciting materials, and they have a huge potential for use in future products that need the cheap and rapid transfer of information," he says.

Posted: Nov 08,2020 by Roni Peleg