Simulations suggest that magnetic skyrmions could form the basis of ultra-low-power-consumption devices that mimic the memory and learning functions of neural synapses.
Despite advances in computer power, there are still tasks that are best done by biological brains. Efforts to emulate the way the brain is wired have led to work on "artificial synapses" as connections for use in "neuromorphic" computers that try to emulate the functionality of a biological brain. Researchers in China have now demonstrated that the skyrmion – a type of magnetic quasiparticle – could be used to create energy-efficient synaptic devices.
New challenges are not always best met with old tools, and as challenges go, emulating synaptic connections in a scalable system – the human brain contains hundreds of trillions of synapses – is no mean feat. Synapses do more than connect neurons, they weigh how well neurons are connected through signal spiking and modulation processes that are thought to be the basis of human learning and cognition. While some progress in the development of synaptic devices has been made using phase-change memories, Ag-Si memories and resistive memories, studies of magnetic skyrmions suggest they may be a promising alternative.
Skyrmions are particle-like regions within a field where all of the field vectors point either towards or away from a single point in space. They were originally proposed in the 1950s by British physicist Tony Skyrme to explain aspects of particle physics. Researchers have since discovered that some collective excitations of electron spins in solids behave much like skyrmions, and the first observation of a magnetic skyrmion lattice was reported in 2009. These solid-state skyrmions could be potentially useful in next-generation electronics and spintronics.
Physics World: Magnetic skyrmions could help make low-energy artificial 'brains'
Anna Demming is editor of nanotechweb.org