Probing Hot-Electron Dynamics at Surfaces with a Cold Scanning Tunneling Microscope

Hot-electron dynamics at noble metal surfaces

The dynamics of excited electronic states at Ag surfaces is studied by evaluating the quasiparticle selfenergy within the GW approximation. The screened Coulomb interaction W is shown to be sensitive to the spatial variation of s-d screening near the surface. In the region of s-electron spill-out electronic damping is stronger than in the bulk due to the reduced s-d polarization, giving rise to...

Simulating Scanning Tunneling Microscope

the scanning electron microscope

it is only thirteen years since the scanning electron microscope has been available commercially. yet, even in this short period of time, this instrument has been a powerful tool in the investigation of topography, electrical and magnetic properties, crystal structure, cathodoluminescent characteristics etc. of solid specimens. today, this type of microscope has opened its place alongside the c...

Tunneling rates in electron transport through double-barrier molecular junctions in a scanning tunneling microscope.

The scanning tunneling microscope enables atomic-scale measurements of electron transport through individual molecules. Copper phthalocyanine and magnesium porphine molecules adsorbed on a thin oxide film grown on the NiAl(110) surface were probed. The single-molecule junctions contained two tunneling barriers, vacuum gap, and oxide film. Differential conductance spectroscopy shows that electro...

Cell organelles at uncoated cryofractured surfaces as viewed with the scanning electron microscope.

A method of direct visualization of cell organelles by scanning electron microscopy (SEM) is described. Plant and animal tissues fixed in glutaraldehyde and osmium tetroxide are treated with the ligand thiocarbohydrazide and a second osmium tetroxide solution, to increase their osmium content. Tissues are then dehydrated, infiltrated with an epoxy monomer, and together solidified with dry ice a...