Science & Technology, UK (Commonwealth Union) – Graphene is a material that has been creating a lot of buzz in recent years. It is a one-atom-thick layer of carbon atoms arranged in a hexagonal lattice pattern, which is believed to have remarkable properties that make it suitable for a wide range of applications.
The unique properties of graphene have been seen as having the potential to revolutionize many industries, including electronics, energy storage, biomedicine, and more. Graphene-based materials have already been used in the production of flexible touchscreens, wearable devices, and solar cells. They are also being explored for their potential in water filtration, batteries, and even in the development of artificial organs.
One of the biggest challenges is scaling up the production of high-quality graphene at an affordable cost. There is also a lack of standardized testing and characterization methods for graphene-based materials, which makes it difficult to compare and evaluate different products.
Graphene’s unique properties are believed to make it an excellent material for use in biomedicine. Graphene-based materials have been used in the development of biosensors, drug delivery systems, and even in the creation of artificial organs. Graphene’s ability to conduct electricity and heat could be used to create implantable sensors that can monitor a patient’s vital signs in real-time. A re-evaluation of graphene maybe needed according to a new study.
Scientists from The University of Manchester have shown record-high magnetoresistance that is seen in graphene under ambient conditions.
Materials that strongly alter their resistivity under magnetic fields are much in demand for various applications such as for cars as well as for computers consisting of many small magnetic sensors. These materials are limited, and most metals and semiconductors alter their electrical resistivity simply by a minute fraction of a percent at room temperature as well as in practically viable magnetic fields. For monitoring a strong magnetoresistance response, scientists generally cool materials to liquid-helium temperatures so electrons within may scatter at a lower level and may follow cyclotron trajectories.
Currently a study team led by Professor Sir Andre Geim has discovered that good old graphene that seemed to be evaluated in every detail in the last 2 decades show a remarkably strong response, reaching over 100 percent in magnetic fields of standard permanent magnets. This is a record magnetoresistivity with every known material, as indicated by scientists.
Commenting on the most recent findings on graphene, Sir Andre Geim indicated that individuals working on graphene like himself always felt that this gold mine of physics should have been made use of a long time back. The material repeatedly proves us wrong seeking yet another incarnation. He also indicated that presently he has to admit again that graphene is dead, and long live graphene.
For the achievement of this scientists utilized high-quality graphene and changed it to its intrinsic, virgin state where there were just charge carriers excited due to temperature. This formed a plasma of rapidly moving “Dirac fermions” that demonstrated a surprisingly increased mobility despite regular scattering. Both high mobility and neutrality for the Dirac plasma are essential components for the indicated giant magnetoresistance.
On top of the record magnetoresistivity, the scientists have had further discovered that, at increased temperatures, neutral graphene became a so-called “strange metal”. This was the name assigned to materials where electron scattering becomes ultimately more rapid, being determined just by the Heisenberg uncertainty principle. The behavior of strange metals is poorly known and stays a mystery presently under investigation across the world.
Scientists indicated that the study advances the further mystery to the field by demonstrating that graphene displays a giant linear magnetoresistance in fields above a few Tesla, which is weakly temperature dependent. This high-field magnetoresistance is again record-breaking.
The work of the present study gives vital clues about origins of the strange metal behavior and of the linear magnetoresistance. This opens the possibility, of the mysteries to be finally solved.
