Subharmonic gap structure in superconducting scanning tunneling microscope junctions

Effect of rf on subharmonic gap structure in superconducting junctions

2014 The rf-power dependence of the structure in the current-voltage characteristic located at the voltage V = (2 0394 ± nhv)/me has been measured and found very similar to the familiar microwave-assisted tunneling (m = 1). 2 0394 is the superconducting energy gap, v the applied frequency, m = 1, 2, 3, ... and n = 0, 1, 2, ... That is, the variation with power of all these structures is found c...

Subharmonic energy-gap structure in superconducting weak links.

Simulating Scanning Tunneling Microscope

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...

Vacuum tunneling of superconducting quasiparticles from atomically sharp scanning tunneling microscope tips

We report on the study of atomically sharp superconducting tips for scanning tunneling microscopy and spectroscopy. The results clearly show vacuum tunneling of superconducting quasiparticles from atomically sharp tips. Observed deviations of the energy gap of the superconducting tip from its bulk value are attributed to the proximity effect. We show that a combination of a superconducting tip ...