9 septiembre 2014
Truly two-dimensional objects are rare. Even a thin piece of paper is trillions of atoms thick. When physicists do succeed in producing 2D systems, quantum interactions can lead to new phenomena and Nobel prizes. Two examples: graphene — single-atom-thick sheets of carbon atoms — has unique mechanical, electrical, and optical properties; and two-dimensional electron gases (2DEG) — planar collections of electrons supported at the interface between certain semiconductors such as gallium arsenide — allow the observation of such emergent behaviors as the quantum Hall effect and the spin Hall effect. Using an overlying bath of ionic liquid, a piece of superconductor — divided by an insulating strip — supports narrow tunnels which permit currents to flow between.
http://feeds.sciencedaily.com/~r/sciencedaily/~3/3h8d6jASU6E/140909162337.htm
