SciCombinator

Discover the most talked about and latest scientific content & concepts.

E Pallecchi, M Ridene, D Kazazis, F Lafont, F Schopfer, W Poirier, MO Goerbig, D Mailly and A Ouerghi
Abstract
Quasi-particle excitations in graphene exhibit a unique behavior concerning two key phenomena of mesoscopic physics: electron localization and the quantum Hall effect. A direct transition between these two states has been found in disordered two-dimensional electron gases at low magnetic field. It has been suggested that it is a quantum phase transition, but the nature of the transition is still debated. Despite the large number of works studying either the localization or the quantum Hall regime in graphene, such a transition has not been investigated for Dirac fermions. Here we discuss measurements on low-mobility graphene where the localized state at low magnetic fields and a quantum Hall state at higher fields are observed. We find that the system undergoes a direct transition from the insulating to the Hall conductor regime. Remarkably, the transverse magneto-conductance shows a temperature independent crossing point, pointing to the existence of a genuine quantum phase transition.
Tweets*
1
Facebook likes*
0
Reddit*
0
News coverage*
0
Blogs*
0
SC clicks
1
Concepts
Quantum Hall effect, Hall effect, Spin, Electron, Electric current, Fundamental physics concepts, Magnetic field, Condensed matter physics
MeSH headings
-
comments powered by Disqus

* Data courtesy of Altmetric.com