Researchers tilt nanomagnets to pack memory systems onto microprocessors
Tue 4 Aug 2015
A team of researchers at the University of California, Berkeley, is investigating ways to switch the polarisation of nanomagnets – creating the possibility of combining long-term magnetic storage into integrated circuits, increasing the speed and energy efficiency of computing.
Published in the journal ‘Proceedings of the National Academy of Sciences’ on August 3rd, the research paper outlines how high-density storage could now be moved from hard disks and installed directly into calculation-performing chips. The scientists hope this breakthrough will allow computers to turn on instantly, operate more rapidly, and use significantly less power.
“To reduce the power draw and increase the speed, we want to be able to manufacture a computer chip that includes memory so that it is close to the computational action,” explained research lead Sayeef Salahuddin, associate professor of electrical engineering and computer sciences.
“However, the physics needed to create long-term storage are not compatible with integrated circuits.”
Up until now computational circuits and magnetic storage has always been kept separate, as creating a magnetic field for long-term memory demands power and space. These memory types include the computer’s hard disk drive, and random-access memory (RAM) on the central processing unit’s (CPU) integrated circuits. A large part of the energy consumed in computing is therefore spent on transferring data from memory, which generates lots of heat.
In past research, Salahuddin and the UC Berkeley team found that directing an electrical current through the metal tantalum creates polarity in the magnets without an external magnetic field. Additionally, packing the nanomagnets tightly and aligning them perpendicularly onto a chip with a vertical orientation negated the switching effects of tantalum.
“We found that by tilting the magnet – just 2 degrees was enough – you get all the benefits of a high-density magnetic switch without the need for an external magnetic field,” Salahuddin added.