Researchers at the National Graphene Institute in Manchester have conducted a series of experiments on electrons in graphene.
In graphene, electrons move in unusual ways. The results of the tests have shown how — within a specific range of temperatures — electrons move and collide so frequently that they eventually display fluid-like behaviour, like slow-pouring honey.
This fluid is more conductive than ballistic electrons — electrons that move throughout the material in a scattering-pattern way, and are only reflected by imperfections. Commonly, the scattering pattern impacts flow, making a material less conductive. However, the electric current in graphene has not flown along the applied electric field, as in other materials. Rather than staying separated, the electrons moved backwards forming whirlpools where circular currents appear. Such behaviour is familiar for conventional liquids such as water which makes whirlpools when flowing around obstacles.
The scientists have measured the viscosity of this strange new liquid in graphene. Surprisingly, it can be 100 times more viscous than honey, even at room temperature.
Additional disorder always creates extra electrical resistance. In this case, disorder induced by electron scattering actually reduces resistance.
One-atom thick material graphene has a reputation for its many superlative properties and exceptionally high electrical conductivity. Graphene can be used for a number of things and is thought to be one of the key components in the development of faster and more powerful quantum computers.
The scientific breakthrough is important for understandings of how materials work at the increasingly smaller sizes required by the semiconducting industry, as such whirlpools are more likely to appear at micro and nanoscale. This means we need to learn more about how electrons flow in the graphene, in order to design nano-electronic circuits.
Surely graphene-based circuits will be pivotal in our advancement of electrical technologies, with the clear benefits driving forward research into the physics of conductive materials.