Since the discovery that graphene, the two dimensional carbon allotrope, can be isolated and incorporated into electronic devices intense research efforts have been triggered. Driving forces behind the experimental and theoretical studies of graphene are, e.g., the exceptional electronic properties, in particular the high electron mobilities, the long spin coherence lengths and the possibility to […]
Chemistry • Condensed matter • Quantum physics • Theoretical physics
Imagine there exist a material in which an electron could be split into two quasiparticles. These two quasiparticles both would carry electric charge, move in opposite directions but could not move backwards. Furthermore these quasiparticles would be massless. And we can give them a fancy name, Weyl fermions. This seems to be at odds with […]
A topological insulator is a material in which there is order associated to topology, i.e., the surface can conduct electricity but the bulk of the material is an insulator. In these last years topological insulators have received the attention of a large area of the scientific community thanks to their exotic properties. They are promising […]
Author: Tommaso Francese is a Ph.D. student (ITN-EJD-TCCM) at Universitat de Barcelona Every year the amount of data produced is of the order of magnitude of the Avogadro’s constant, thus 6.028×10 23 . Let’s say that it is more or less the quantity of hydrogen atoms contained in 1 gram. This trend is supposed to […]
In order to study new solid state magnetic properties appropiate new laboratory models are needed. In particular, there is a necessity for a substrate to investigate new forms of magnetic coupling with nanoscale ferromagnets and the exotic physics at the interface with semiconductor or superconductor materials. Now a team of researchers from DIPC and some […]
A new vista in spintronics was opened in 2004 with the observation of the spin Hall effect in GeAs at 20 K by David Awschlom and his group. In the spin Hall effect the electrons of a charge current flow in a nonmagnetic conducting material in the absence of an external magnetic field. An applied […]
The interactions between moving charges and magnetic fields can be quite complicated; more if we consider the quantum effects. One example is the collection of Hall effects. There are analogues of these effects for spin and the detection of the most sophisticated one in graphene, where, at least, it should not be strong, is something […]
Computer science • Condensed matter • Materials • Physics • Quantum physics
When quantum computing comes, it very likely will rely for the fast storage and processing of information on spintronics. Spintronics (from spin transport electronics) is a branch of technology that specifically makes use of quantum-mechanical spin, and especially of the transport of that spin, in electronic devices. Spin is the part of the total angular […]
Graphene is a material with outstanding electronic characteristics. Many of them arise from the cone-like dispersion of charge carriers near the Fermi level (at which the occupation probability of energy levels is 0.5), where electrons behave as relativistic Dirac fermions, i.e., as if they had no mass. This excellent video from toutestquantique.fr summarizes them very […]
An electric current can be visualized as a flow of electrons through a conducting piece of material. The less the resistance the material structure opposes to the flow of electrons the better a conductor it is. A part of this resistance appears at the surface of the material, where the electrons first encounter it; as […]