Scientists at Leeds University have discovered a method to create magnetism in metals that aren’t naturally magnetic, opening up the possibility of using a range of abundant metals for magnetic applications.
The study, published in the journal Nature, details a way of altering the quantum interactions of matter in order to adjust the outcome of a mathematical equation called the Stoner Criterion, which determines whether elements are magnetic.
Magnets have multiple industrial and technological uses, including power generation in wind turbines, memory storage, and medical imaging. However, only three metals – iron, cobalt and nickel – are naturally ferromagnetic, meaning they remain magnetic in the absence of a field.
“Having such a small variety of magnetic materials limits our ability to tailor magnetic systems to the needs of applications without using very rare or toxic materials,” said Tim Moorsom from the School of Physics & Astronomy at Leeds University, co-lead author on the paper.
“Having to build devices with only the three magnetic metals naturally available to us is rather like trying to build a skyscraper using only wrought iron. Why not add a little carbon and make steel?”
In the new study, the researchers have shown how to alter the behaviour of non-magnetic materials by removing some electrons using an interface coated with a thin layer of the carbon molecule C60, which is also known as a ‘buckyball’.
The movement of electrons between the metal and the molecules allows the non-magnetic material to overcome the Stoner Criterion and become magnetic. According to the researchers, the discovery opens up new possibilities across a host of different industries.
“Being able to generate magnetism in materials that are not naturally magnetic opens new paths to devices that use abundant and hazardless elements, such as carbon and copper,” said co-lead author Fatma Al Ma’Mari, also from the University’s School of Physics & Astronomy.
“Future technologies, such as quantum computers, will require a new breed of magnets with additional properties to increase storage and processing capabilities. Our research is a step towards creating such ‘magnetic metamaterials’ that can fulfil this need.”