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Fractals in nanoelectronics, neural sensors and solar cells

Fig 3(a) a fractal neuron, (b-d) fractal interconnects designed to stimulate and sense neuronal signals

Nanoelectronic devices approach one billionth of a meter in size (50,000 times smaller than a human hair). Smaller than today’s commercial devices and made from purer materials, nano-devices are expected to revolutionize the technologies that underpin society.Ballistic nanoelectronic devices are made from materials so pure that the electrical current travels through the solid much like bullets fly through the air! Although impurities in the material are minimized in these devices, they have a profound effect on device performance. My research investigates how impurities induce chaos in the electricity by scattering the flow of electrons in the current. This chaotic scattering causes the electricity to flow along fractal patterns through the devices, much like a river splitting into fractal tributaries. Intriguingly, quantum mechanics allows the electrons to behave both like waves and particles, resulting in the highly topical phenomenon ‘quantum chaos’.

My research of quantum chaos and the resulting fractal electricity is aimed at understanding the basic principles of electricity at the nano-scale and also how to exploit this novel behavior to produce faster and more powerful electronic devices.Given that electricity wants to flow along fractal pathways, we are building devices that connect together to form fractal shapes. These fractal circuits are constructed using two “self-assembly” growth processes: one process deposits gold nanoparticles onto tangled DNA strands, the other grows ‘nanoflower’ circuits from nanoclusters (see left image). Self-assembly represents an efficient and ‘green’ approach to constructing devices.

In addition to novel fractal transistors and sensors, we are developing fractals circuits for human implants and solar cells. In each case, we use the principle of biomimicry to exploit the functionality of nature’s fractals to provide technological advances. The fractal circuits are ideal for bioeletronics because they mimic the neurons they are designed to stimulate and measure. They also replicate the light-harvesting properties of fractal trees for the solar cells. These two projects represent the most important targets for future physics research – safeguarding human health and the Earth’s environment. For example, fractal electronics could address neurological disorders such as Parkinson’s disease and depression, and also improve nerve connections to prosthetic limbs.

Selected Recent Publications And Media

Fractal implants for sensing and stimulating neuronal signals:

Fractal Solar Cells:

Fractal Nano Circuits:

Film-Boiling Liquids:

Ballistic Optical Devices:

Ballistic Electronic Devices: