TY - JOUR TI - Scanning tunneling microscopy and spectroscopy studies of graphene DO - https://doi.org/doi:10.7282/T3833QT6 PY - 2012 AB - In the two-dimensional (2D) lattice of graphene, consisting of carbon atoms arranged in a honeycomb lattice, the charge carriers are described by a Dirac-Weyl Hamiltonian. Seeking to understand their unique nature, this thesis presents results of scanning tunneling microscopy (STM) and spectroscopy (STS) experiments at low temperatures and in magnetic fi eld. These techniques give access, down to atomic scales, to structural information as well as to the electronic properties of graphene. The main findings include the observation of quantized Landau levels (LL) in the presence of magnetic field, their dependence on carrier density and e ffects of charged impurities and other disorder on the LL spectrum. Twisting graphene layers away from the equilibrium Bernal stacking leads to the formation of Moir e patterns that signi ficantly alter the electronic properties of graphene stacks. The second part of the thesis discusses the eff ects of such rotations on the electronic properties as a function of twist angle. KW - Physics and Astronomy KW - Graphene--Electric properties KW - Scanning tunneling microscopy KW - Graphene--Spectra LA - eng ER -