As we approach the miniaturisation limits of conventional electronics, alternatives to silicon-based transistors are being hotly pursued.
Inspired by the way living organisms have evolved in nature to perform complex tasks with remarkable ease, a group of researchers from Durham University in the UK and the University of São Paulo-USP in Brazil is exploring similar “evolutionary” methods to create information processing devices.
In the Journal of Applied Physics, the group describes using single-walled carbon nanotube composites as a material in “unconventional” computing. By studying the mechanical and electrical properties of the materials, they discovered a correlation between the Nanotubes’ concentration, viscosity, conductivity and the computational capability of the composite.
Mark K. Massey, research associate, School of Engineering and Computing Sciences at Durham University said;
Instead of creating circuits from arrays of discrete components (transistors in digital electronics), our work takes a random disordered material and then ‘trains’ the material to produce a desired output.
This emerging field of research is known as “evolution-in-materio,” a term coined by Julian Miller at the University of York in the UK What exactly is it? An interdisciplinary field blends together materials science, engineering and computer science. Although still in its early stages, the concept has already shown that by using an approach similar to natural evolution, materials can be trained to mimic electronic circuits–without needing to design the material structure in a specific way.
“The material they are a mixture of carbon nanotubes and polymer, which creates a complex electrical structure. When voltages (stimuli) are applied at points of the material, its electrical properties change. When the correct signals are applied to the material, it can be trained or ‘evolved’ to perform a useful function.”
While the group doesn’t expect to see their method compete with high-speed silicon computers, it could turn out to be a complementary technology. And with more research, it could lead to new techniques for making electronics devices. The approach may find applications within the realm of “analog signal processing or low-power, low-cost devices in the future.
The next stage of the group’s research will be to investigate evolving devices as part of the material fabrication “hardware-in-the-loop” evolution. “This exciting approach could lead to further enhancements in the field of evolvable electronics,” said Massey.