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First results on the LT-UHV-4STM (4 points) at CEMES-CNRS

Published on the 1st February 2016 in Eur. Phys. J. Appl. Phys.

by PREVOTS Evelyne - published on , updated on

The future nanocar race will take place on this machine.

Scientists at CEMES have recently pushed to the limits their new ScientaOmicron low-temperature tunneling microscope (LT-UHV 4-STM) installed in October 2014 at Pico-Lab. This unique instrument is equipped with 4 STM scanners capable of operating on the same surface and in parallel. On the surface Au (111) and at 4.3 K, CEMES researchers managed to reproduce for the first time a series of experiments now performed on the most stable single tip LT-UHV STM around the world. The STM images produced by the 4 scanners on the same surface (independently or in parallel) have a DZ stability better than 2 pm per STM scanner. The minimum inter STM tip apex distance is a few tens of nanometers and is measured using a high resolution UHV SEM equipping this instrument as well. With this stability, single atom manipulations were carried while recording the famous corresponding manipulation signals to recover the pushing, pulling and sliding atom manipulation modes per STM tip. Electrical contact experiments on a single atom were also performed to record the current-voltage characteristic (I-V) of a single Au atom exactly in contact and demonstrating a quantum of conductance. No average over multiple I-V characteristics was required for these measurements. Floating surface two-points conductance measurements were also conducted on the Au(111) surface using a lock-in technique to locate the Au(111) surface states near the Fermi level.


The results of the CEMES scientists show how this new instrument is exactly 4 times the most accurate tunneling microscope in the world. Such equipment will now be used to measure the electronic conductance of a single atomic wire constructed atom by atom in planar configuration and also the motive power of a molecule motor about 1 nm in rotor diameter. The future spring 2017 international molecule car race will take place on this instrument.

JPEG - 102.7 kb
A top view of the LT-UHV 4-STM head used in this work and a pseudo 3D STM image (5.12 nm x 5.12 nm)
of the letter C constructed atom by atom with 6 Au atom on an Au(111) reconstructed surface.
The single atom manipulations and the STM images were obtained on the scanner 3 of this instrument
for I = 50 pA, V = 500 mV with ΔZ = 0.12 nm. For the single Au atom manipulations,
the resistance of the tunnel junction is 333 KΩ



Imaging, single atom contact and single atom manipulations at low temperature using the new ScientaOmicron LT-UHV-4 STM

Jianshu Yang1, Delphine Sordes1,2, Marek Kolmer3, David Martrou1 and Christian Joachim1,4a

1 Nanoscience Group & MANA Satellite, CEMES/CNRS, 29 rue Marvig, BP 94347, 31055 Toulouse Cedex, France

2 CEATech Midi-Pyrénées, Campus INSA, Bât. GM 135 avenue de Rangueil, 31400 Toulouse, France

3 Centre for Nanometer-Scale Science and Advanced Materials, NANOSAM, Faculty of Physics, Astronomy and Applied Computer Science, Jagiellonian University, Lojasiewicza 11, 30-348 Krakow, Poland

4 International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan

Eur. Phys. J. Appl. Phys. (2016) 73: 10702



Dr Christian Joachim : christian.joachim at cemes.fr