Created superconducting transistor of graphene

American scientists from the National Laboratory L. Berkeley Department of Energy failed to conduct an experiment, which resulted in the construction of structures of graphene He showed the ability to move from one phase state to another when exposed to certain voltage.

This is the first successful experiment, so to talk about its commercial implementation is still too early.

The results of this study have been published in a scientific journal Nature.

The device design

Established design that mimics a transistor implemented in three graphene layers (one layer has a thickness in the atom) and two layers of boron nitride, which is packed graphene on both sides.

And by the outer layers are bonded boron nitride electrodes. To experiment failed, it was necessary to cool the resultant structure 5 Kelvin.

In this case, the control voltage for a long time been forced to pick up experimentally, since the theory of superconductivity at high temperatures still has huge gaps.

As a result, at a certain tension generated "transistor" cease to pass an electric current - closed, and once started increase capacity or more lower temperature (reduced below 40 mK), transformed into a superconductor and started again pass electricity.

In this case, the physics of the process is

Boron nitride has a hexagonal structure greatly resembles the structure of the graphene, but since the distance between atoms is great, then a match occurs only in some areas.

Thus, when stacked one on another structure, moire superlattice formed with periodically repeated portions (about 10 nm), where the coincidence cells. It is in these areas, and allowed to form a transistor transitions.

In this case, when the temperature is 5 Kelvin and up to a certain voltage value formed by the structure is no more than a Mott insulator. In theoretical calculations of electron conductivity must be present, but because of the strong electron correlation is not observed.

Output from this state structure can be exposed to a strong electromagnetic field or even longer to cool the structure.

Under these effects in localized regions of the electrons cease to hold each other and fall down as if in wells formed in the areas where the crystal lattice match and thereby graphene transistor opens.

Once the technology is fully run-in and displayed on the commercial use of it It allows to perform electronic devices even smaller and thus their cost is more below.

If you like the article, then it Like to vote and thank you for your valuable attention!