Atomically precise electrical probing

Two-probe STM experiments at the atomic level

The unprecedented stability and drift performance of the LT NANOPROBE opens the route towards multi-probe transport measurements of planar atomic or molecular nano-scale systems.

So far the stability of single atom contacts and probe navigation with real atomic precision has only been accessible by single probe SPM experiments. Parallel STM imaging of probes is crucial to control the individual points of contact and to identify the minimal distance between probes by inter-probe tunnelling.


Video showing the lateral drift

The sequence shows the lateral drift over a period of 2 hours.
The displacement of the adsorbate is only 2.5 Angstroem within 2 hours.
(Scan area 20 nm x 20 nm)


STM atom manipulation on Ag(111) at T<5 K

Recent results of atom manipulation experiments on Ag(111).

- First step: looking for clean and large terraces for manipulation experiments.
- Afterwards the tips was crashed softly into the Ag surface and afterwards retracted.
- During the tip crash at voltage of 2-3V was applied to the tip.
- After this you can find a lot of single Ag atoms and clusters on the surface.
- these atoms and clusters can be manipulated.


STM Performance at 4.5 K

STM results to demonstrate the STM performance of the 4 probe instrument in order to give an idea what type of experiments are possible with this instrument. It starts with simple STM measurements of atomic steps and herringbone structure. The measurements were carried out on Au(111) and Ag(111) surfaces at 4.5K.


STM on Au(111) at 4.5 K with different tunneling current setpoints

Series of STM topography images measured at high and very low tunneling currents. The left image was taken at a tunneling current set-point of 40 nA, the image in the middle at 10 pA and the right image at only 2 pA!