Electronic and Optical Properties of Graphene

摘要: We investigate the electronic and optical properties of various one two dimensional graphene based materials. Using tight binding approximation, we calculate dispersions these systems. Green’s functions, then evaulate dielectric function within random phase approximation (RPA), corresponding collective excitation spectrum for armchair nanoribbons. also Kubo formula-based conductivity single layer graphene, bilayer nanoribbons, stretched graphene. For Dirac third order nonlinear conductance (a correction to ‘universal’ conductivity, as well a frequency tripling term) finally effect electron-LO phonon scattering on at temperatures doping levels. There are several results particular interest. predict rotonlike mode in non-Dirac demonstrate magnitude enhancement an entire subclass nanoribbons terahertz-far infrared regime. A strong under moderate field strengths room temperature is derived. Finally, stretching induced hall chirality dependent anisotropy conservative conditions predicted. find that materials remarkably robust highly tunable, particularly terahertz far-infrared Furthermore, prediction roton-like minimum spectra ribbons makes part extremely small materials, represents opening potentially huge new fundamental research. List Publications Refereed Journal Articles 1. Wright A.R., Zhang C. “Dynamic with electronLO-phonon interaction” Phys. Rev. B. 81, 165413 (2010). 2. Cao J.C., “Enhanced regime” Lett. 103, 207401 (2009). 3. A.R. “Stretching Hall current graphene” App. 95, 163104 (2009), selected November 2, 2009 issue Virtual Nanoscale Science $ Technology. 4. A. R., Xu X. G., J. C., “Strong response regime”, Applied Physics Letters 072101 August 31, & 5. Liu F., “The next nearest neighbour coupling Nanotechnology 20, 405203 6. J., Ma Z., magnetic field”, 93 (4), 041106, (2008).