In recent years, physicists have discovered materials that are able to switch their electrical character from a metal to an insulator, and even to a superconductor, which is a material in a friction-free state that allows electrons to flow with zero resistance. These materials, which include “magic-angle” graphene and other synthesized two-dimensional materials, can shift electrical states depending on the voltage, or current of electrons, that is applied.
Click here for original story, Physicists find direct evidence of strong electron correlation in a 2D material for the first time
Source: Phys.org