Nov 29, 2013
Logic operations on a nanomagnetic staircase
Researchers at the University of Cambridge report on the first experimental demonstration of sharp magnetic kink soliton propagation, injection and annihilation in a multilayer consisting of ultrathin (<1 nm) metal layers deposited using a technique called magnetron sputtering. The soliton forms a digital shift register (or staircase) based on magnetic layers with near-atomic size stretching vertically above a silicon substrate. When an external magnetic field is applied, the bits (solitons) can be shifted together as a whole and then manipulated individually. They can even be brought together to perform logic operations.
Spintronics, which exploits the spin of an electron as well as its charge, is an exciting new nanodiscipline that has emerged in the last 20 years. However, if viewed critically, spintronics cannot yet be described as having had a revolutionary impact – most of the concepts currently discussed within the research community are about improving the efficiency of existing devices or adding a new element of functionality to a traditional concept. Three-dimensional electronics is one area in which spintronics could truly be revolutionary, by actively enabling the use of the third (that is, vertical) dimension for logic devices.
The experiment described in this work is one of the highest-level demonstrations of logic operation ever performed on data in the magnetic state and brings ultrahigh-density all-magnetic microprocessors based on spintronics closer to becoming a reality.
More information about the research can be found in the journal Nanotechnology (in press).
About the author
Dr Ir Reinoud Lavrijsen and colleagues performed this work in Prof. Russell Cowburn's Thin Film Magnetism Group at the Cavendish Laboratory of the University of Cambridge, UK. Dr Lavrijsen is currently a VENI research fellow in the Physics of Nanostructures (FNA) Group at the Eindhoven University of Technology, The Netherlands, where he is exploring different torques to efficiently switch ultrathin nanomagnets.