Graphene - The Strongest

Graphene:-

Graphene which is about one atom thick is found to be the world's strongest material according to a latest information by scientists. It is made of carbon atoms. It is stronger than diamond which is also made of carbon.It conducts electricity 100 times better than any other materials existing now.It is expected that this graphene would replace silicon in computer chips. But it would take some time to replace as every one is known and using silicon only. Scientists celebrated it as a boon by god to the science.The right side image shows a ultra strong paper made of graphene.

Structure of Graphene:-


Graphene is closely related to buckyballs and polycyclic aromatic hydrocarbons.Some researchers believe that graphene transistors could operate in the terahertz range, about 1000 times faster than conventional silicon ones. The reason is that electrons move much faster through graphene. Unfortunately the difference in conductivity between the "on" and "off" states is less for graphene. This makes it harder to work with.

Electrons can very easily travel along the carbon sheet making graphene an extremely good electrical conductor. This conductivity suggests that graphene could have a future in the semiconductor industry, with the fabrication of high speed transistors.

Shot Noise In Graphene:-

By biasing a conductor that has sizes smaller than the electron-phonon inelastic scattering length, it is possible to study the out of equilibrium current noise generated by the system: such noise is called shot noise . These current fluctuations are due to the discreteness of charge. By probing shot noise, one can collect informations about disorder, interactions, contact quality, or carrier statistics for example. We have studied shot noise in short and large graphene strips . We used two ways to extract the Fano factor, using the formula defined in and using a tunnel junction to calibrate the noise of our devices .



We use a home made set-up especially design to work at high frequency. In perfect short and wide graphene strips (W/L ≥ 3), for heavily doped graphene leads, at the Dirac point both minimum conductivity and Fano factor are expected to reach universal values of 4e2/πh and 1/3 respectively .