Jason Horng,1 Chi-Fan Chen,1 Baisong Geng,1 Caglar Girit,1 Yuanbo Zhang,2 Zhao Hao,3,4 Hans A. Bechtel,3 Michael Martin,3 Alex Zettl,1,5 Michael F. Crommie,1,5 Y. Ron Shen,1,5 and Feng Wang1,5,* 1Department of Physics, University of California at Berkeley, Berkeley, California 94720, USA 2Department of Physics, Fudan University, Shanghai 200433, China 3Advanced Light Source Division, Lawrence B...

We have analyzed available optical data for Au in the mid-infrared range which is important for a precise prediction of the Casimir force. Significant variation of the data demonstrates genuine sample dependence of the dielectric function. We demonstrate that the Casimir force is largely determined by the material properties in the low frequency domain and argue that therefore the precise value...

Graphene is a promising material for applications in aqueous electrolyte environments. To explore the impact of such environments on graphene’s electrical properties, we performed Hall bar measurements on electrolyte-gated graphene. Assuming a Drude model, we find that the room temperature carrier mobility reaches 7,000 cm 2 /Vs, the highest mobility recorded for graphene in an aqueous electrol...

A novel, two-parameter modification of a Drude model, based on fractional time derivatives, is presented. The dielectric susceptibility calculated analytically and simulated numerically, showing good agreement between theoretical description numerical results. absorption coefficient wave vector are shown to follow power law in the frequency domain, which common phenomenon electromagnetic acoust...

We numerically investigate the distribution of Drude weights D of many-body states in disordered onedimensional interacting electron systems across the transition to a many-body localized phase. Drude weights are proportional to the spectral curvatures induced by magnetic fluxes in mesoscopic rings. They offer a method to relate the transition to the many-body localized phase to transport prope...

The optical conductivity of quasicrystals is characterized by two features not seen in ordinary metallic systems. There is an absence of the Drude peak and the interband conductivity rises linearly from a very low value up to normal metallic levels over a wide range of frequencies. The absence of a Drude peak has been attributed to a pseudogap at the Fermi surface but a detailed explanation of ...

The effect of grain boundaries on the electron relaxation rate is significant even for large area noble metal films and more so for plasmonic nanostructures. Optical spectroscopy and X-ray diffraction show a substantial improvement in plasmon resonance quality for square-particle nanoantennas after annealing due to an enlarged grain size from 22 to 40 nm and improved grain boundaries described ...

The onset and decay of photoconductivity in bulk GaAs has been measured with 200-fs temporal resolution using time-resolved THz spectroscopy. A low carrier density (,2310 cm) with less than 100-meV kinetic energy was generated via photoexcitation. The conductivity was monitored in a noncontact fashion through absorption of THz ~far-infrared! pulses of several hundred femtosecond duration. The c...