Honeycomb shaped nano-magnets could yield new type of electronics

While many modern data storage devices rely on the ability to manipulate the properties of tiny individual magnetic sections, their overall design is often limited by the way these magnetic 'domains' interact when they are close together. Now, the Imperial team has demonstrated that a honeycomb pattern of nano-sized magnets, in a material known as spin ice, introduces competition between neighbouring magnets, and reduces the problems caused by these interactions by two thirds. They have also shown that large arrays of these nano-magnets can be used to store computable information. The arrays can then be read by measuring their electrical resistance. The scientists have so far been able to 'read' and 'write' patterns in the magnetic fields, and a key challenge now is to develop a way to utilise these patterns to perform calculations, and to do so at room temperature. At the moment, they are working with the magnets at temperatures below -223°C. Dr Will Branford, who led the team, said: "Electronics manufacturers are trying all the time to squeeze more data into the same devices, or the same data into a tinier space for handheld devices like smart phones and mobile computers. However, the innate interaction between magnets has so far limited what they can do. "In some new types of memory, manufacturers try to avoid the limitations of magnetism by avoiding using magnets altogether, using things like flash, memristors or antiferromagnets instead. However, these solutions are slow, expensive or hard to read out. Our philosophy is to harness the magnetic interactions, making them work in our favour." Dr Branford is optimistic that new technology will be available in the next ten to fifteen years. The team's next big challenge is to make an array of nano-magnets that can be 'programmed' without using external magnetic fields.