A team of Manchester University researchers led by Nobel Prize laureate Konstantin Novoselov has described novel properties of 3D graphene stacks.
Although famously two-dimensional, the wonder material, discovered in 2004 by Novoselov and his colleague Andre Geim, is expected to have even more promising properties when arranged into 3D heterostructures.
In the latest issue of the journal Nature Physics, the team led by Novoselov, who was together with Geim awarded the Nobel Prize in Physics in 2010, describes strong interaction between layers in such graphene stacks, which helps the researchers learn how to control the properties of such heterostructures.
“Research on heterostructures is gaining momentum, and such possibilities for controlling the properties of heterostructures might become very useful for future applications,” said Professor Novoselov.
By controlling the relative orientation between graphene and underlying boron nitride – one of the 2D materials and an excellent insulator – the team can reconstruct the crystal structure of graphene. This leads to creation of local strains in graphene and even opening of a band-gap, which might be useful for the functionality of many electronic devices.
“It was extremely exciting to see that the properties of graphene can change so dramatically by simply twisting the two crystals only a fraction of a degree,” said PhD student Colin Woods, who carried out the vast majority of the work.
“Generally, the previous model, used to describe the sort of interaction which has been observed in our experiments, describes only the 1-dimensional case, but even there it produces very nontrivial solutions. We hope that our system will push the mathematical development of the model to two-dimensions, where even more exciting mathematics is to be expected.”
The discovery of graphene – a flat two-dimensional crystal of carbon only one atom thick – spurred excitement in the scientific community, which believes it will pave the way for next generation electronics. The so called wonder material can serve as both – a conductor and an isolator and can be transparent or optically active.
The 3D graphene hetorustructures, already explored in the form of tunnelling transistors, resonant tunnelling diodes and solar cells, are believed offer yet unforeseen qualitative properties.