ICTP graphene research published
Study of strongly interacting electron-hole plasma has applications for nanotechnology
Markus Müller of ICTP's Condensed Matter and Statistical Physics section, along with researchers from Iowa State University and Harvard, have discovered a property related to graphene's near quantum criticality that could have potential applications in graphene-based nanoelectronics.
The research focussed on the shear viscosity (thickness) of clean, undoped graphene. The smaller the ratio of the latter to the entropy density ratio, the more strongly the excitations in a quantum fluid interact. Using a quantum kinetic theory, the researchers found that the quantum criticality of graphene makes this ratio smaller than in many other correlated quantum liquids. Furthermore, the ratio comes close to values observed in quark-gluon plasma, with which graphene shares many similarities. The unusually small viscosity in this electronic system might lead to complex, nearly turbulent current flows in nanodevices, with interesting non-linear current-voltage characteristics.
The research appeared in the 6 July edition of the journal Physical Review Letters, and was featured in the journal's online section devoted to exceptional research, Physics. It was also featured as a research highlight in Nature Nanotechnology.