Bismuth
Ultra-thin flakes of Bismuto have “very surprising” properties: it displays the “anomalous hall effect”, a type of electric current behavior that challenges the known properties of metal.
Ultraphine Flakes of the soft metal bismuth They have “very surprising” magnetic properties, and will be able to make their way to more ecological and efficient electronic devices, according to a study on January 8 at PHC.
Ultra-thin materials, such as graphene, are known for their unique physical behaviors, which led scientists to investigate whether the bismutus could have similar characteristics when reduced to nanometric thicknesses.
Due to the smoothness of the bismutus, the creation of sufficiently thin samples has been a challenge, explains, but Guillaume Gervais and his team at McGill University in Montreall exceeded this obstacle.
The team developed a new technique similar to the use of a cheese graterproducing bismutus flakes with only 68 nanometers thick – less than a thousandth of the thickness of a sheet of paper.
Researchers have tested these ultra-thin flakes in a wide range of conditions, including temperatures ranging from absolute zero to room temperature and magnetic fields thousands of times stronger than normal refrigerated imons.
The bismutus consistently displayed the “anomalous hall effect,” a type of electric current behavior that challenges known metal properties.
Carmine Ortix of the University of Salerno in Italy described the results as “very, very surprising”: existing scientific knowledge suggests that the Bismute should not present this effect, he explains. Even under extreme conditions, such as powerful magnetic fields and variable temperatures, the anomalous hall effect persisted.
Promising in the field of electronics
The persistence of this electromagnetic behavior, even at room temperature, makes the ultra -thin bismuth a promising material for the electronics.
According to Ortix, the relatively low toxicity of Bismuto compared to similar materials further increases its attraction to the development of sustainable technologies.
Although the exact mechanism behind this phenomenon remains a mystery, Gervais speculates that the arrangement of bismutus atoms could condition the movement of electrons in a way governed by a set of mathematical principles called topology.
“I can’t point out a theory that explains this, just a few parts of a potential explanation,” says the scientist.
