3D graphene-like material could lead to super electronics
- 21 January, 2014 19:44
Researchers have discovered a material with a similar electronic structure to graphene that can exist in three dimensions and could lead to faster transistors and more compact, higher capacity hard drives.
The material, a form of the chemical compound sodium bismuthate, is called three-dimensional topological Dirac semi-metal (3DTDS).
An international team led by scientists from Oxford University, Diamond Light Source, Rutherford Appleton Laboratory, Stanford University and Berkeley Lab's Advanced Light Source discovered 3DTDS.
The researchers said the material could be used to make a hard drive that is higher density, faster and uses less energy, "for example turning a 1 terabyte hard drive into a drive that can store 10 terabytes within the same volume."
Graphene is a strong, conductive and flexible material that is made up of a single layer of carbon atoms connected in a pattern of hexagonal shapes. Graphene is stronger than a diamond and conducts electricity better than any previous material. But Graphene is also two dimensional, meaning it is produced in flat sheets about one million times thinner than a sheet of paper.
Unlike Graphene, 3DTDS allows electrons to be assembled in a collective to flow in all directions. More importantly, the electrons on the surface of the material remember their magnetic spin -- a property called magnetoresistance -- that allows data to be stored by reversing the polarity of a bit from positive to negative and vice versa.
Scientists have long searched for a natural 3D counterpart to 2D graphene, and while researchers have theorized about a 3D material with the same properties, the discovery confirms that the material exists. The research paper was published last week in the journal Science.
"The 3DTDS we have found has a lot in common with graphene and is likely to be as good or even better in terms of electron mobility - a measure of both how fast and how efficiently an electron can move through a material," Yulin Chen, of Oxford University's Department of Physics, said in a statement.
"In typical Giant Magnetoresistance Materials (GMR), the resistance changes by a few tens of percent and then saturates, but with 3DTDS it changes 100s or 1000s of percent without showing saturation with the external magnetic field," Chen said.
Now that researchers have proven the highly conductive 3D material exists, Chen said the race is on to find more such materials and their applications, "as well as other materials with unusual topology in their electronic structure."