Excitonic fano resonance in free-standing graphene.

We investigate the role of electron-hole correlations in the absorption of free-standing monolayer and bilayer graphene using optical transmission spectroscopy from 1.5 to 5.5 eV.

Graphene on a hydrophobic substrate: doping reduction and hysteresis suppression under ambient conditions.

The intrinsic doping level of graphene prepared by mechanical exfoliation and standard lithography procedures on thermally oxidized silicon varies significantly and seems to depend strongly on processing details and the substrate morphology. Moreover, transport properties of such graphene devices suffer from hysteretic behavior under ambient conditions. The hysteresis presumably originates from dipolar adsorbates on the substrate or graphene surface.

Fabrication of an array of single-electron transistors for a scanning probe microscope sensor.

A technique for the fabrication of single-electron transistors (SETs) on tips for use in scanning probe microscopy is presented. The tips are micromachined out of an MBE-grown AlGaAs-GaAs heterostructure with a trench within each tip. The SETs are produced by aluminum evaporation and oxidation, and natural shadowing by the trench is used to separate the source and drain electrodes.