Graphene Functionalized with Hydrogen and Fluorine: Electronic Correlations, Magnetism, and Transport

by Prof. Jorge O. Sofo (Physics and of Materials Science and Engineering - The Pennsylvania State University)

Tuesday 10 Feb 2015, 16:00 → 18:00 Europe/Rome

Aula Conversi (Dipartimento di Fisica - Ed. G. Marconi)

For an Electronic Engineer, a material with very high electron mobility that is not significantly degraded by temperature or doping is a dream material. For a Physicist, a material where the magnetism can by controlled by electric fields and the Quantum Hall Effect can be observed at room temperature is a dream material. These two sentences would be enough to capture the attention of an audience, but graphene has even more interesting properties. The material is two dimensional, the electrons follow the dynamics of massless relativistic Dirac Fermions, the carrier density can be changed by orders of magnitude with the application of a gate voltage, and it can be reversibly transformed in an insulator by hydrogenation or fluorination. Covering all this in one seminar would be impossible. Therefore, I will offer a personal selection of topics that emphasize the interplay between experiment, theory, and simulations in order to gain understanding and control on the properties of graphene. Chemical functionalization has resulted in a box of surprises. It opens the way to magnetism, localization, and other interesting phenomena that are unexpected in materials made of carbon. We will review the fascinating magnetic states produced with hydrogenation and fluorination of graphene as well as their influence on its transport properties.