Observation of negative differential resistance in tunneling spectroscopy of MoS2 with a scanning tunneling microscope

Simulating Scanning Tunneling Microscope

Negative Differential Resistance in the Scanning Tunneling Spectroscopy of Organic Molecules

The conductance-voltage spectrum of molecular nanostructures measured by scanning tunneling spectroscopy (STS) is generally assumed to reflect the local density of states of the molecule. This excludes the possibility of observing negative differential resistance (NDR). We report here the observation of NDR in the scanning tunneling microscope (STM) current-voltage (I-V) characteristics of self...

Time-resolved scanning tunneling microscope light emission spectroscopy of Sb2Te3

We have successfully added ps temporal resolution to scanning tunneling microscope (STM) light emission spectroscopy. STM light emission spectra of Sb2Te3 were measured in the configuration that the tip sample gap of the STM is irradiated by a pair of pump and probe laser pulses with a duration less than 2 ps each, and were analyzed as a function of optical delay time between the pump and probe...

Scanning Tunneling Spectroscopy of C36

The local density of electronic states NsEd has been measured on C36 thin films using scanning tunneling spectroscopy (STS). A 0.8 eV energy gap and sharp features in NsEd with widths as small as 0.2 eV can be ascribed to the discrete molecular energy levels predicted for the C36 molecule, broadened by intermolecular interactions. However, a more complete agreement between the experimental resu...

Reproducible Fabrication of Scanning Tunneling Microscope Tips

Reproducible fabrication of Scanning Tunneling Microscope tips is carried out following an electrochemical procedure widely reported. Tips are made from 0.5 diameter tungsten wire. Controlling fabrication parameters (immersion in the electrochemical solution, current-voltage ranges, duration of the process, among others) we achieve aspect ratios of 0.68 and tip radii of 330 nm in the best case....