Researchers have discovered that the behavior of electrons in the material graphene appear more like those typically found in liquids than common metals. The findings, published in the journal Science, could lead to more accurate modeling of certain astronomical bodies and tools for efficient conversion between heat and electricity.
Graphene has found many uses since its discovery in 2004, as it is exceptionally strong and light with high conductivity. Yet, being only one atom thick, it is difficult to study.
In order to perform the experiment, it was essential to get an accurate reading of the electrons’ movements, which could easily be interfered with by forces from the outside environment.
The team from Harvard University and Raytheon BBN Technology accomplished this by taking a very pure form of graphene and insulating it between two layers of hexagonal boron nitride, a compound with a comparable structure to graphene.
They then set off a stream of particles, both positively and negatively charged, on the surface of the graphene. They expected the electrons to move past each other without coming into contact. Instead, it was found that they collided with each other readily, and that the energy flowed through the moving particles like a wave traveling through water.
The discovery indicates that the behavior of electrons in graphene can be described by relativistic hydrodynamics, an area of physics that deals with black holes and other relativistic phenomena. This has never been observed in a metal before now.
This feature of graphene means that it can be used to study similar dynamics that occur in celestial bodies like black holes and supernovae. It could also be used as a material for chips in extremely thin electronics.
The findings also have implications for regular consumers, as they raise the possibility of creating devices that can convert between heat and electricity with high efficiency. One potential application of this function could involve using body heat to power or charge wearable electronics or phones.