Ultra-Low Vibration STM Laboratory
For high precision scanning tunnelling microscopy (STM), we have designed two rooms which are shielded against sound, vibrations and electromagnetic radiation.
Scanning tunnelling microscopes (STM) can not only be used to image surfaces with atomic resolution, but also to record spectra from single atoms. With an STM, it is even possible to move individual atoms and molecules at will. How does this work? A sharp metal tip is scanned across the sample surface, thereby recording a profile of the surface structure and revealing information about its local electronic properties. If the interaction between tip and sample is strong enough, the tip can move single atoms at the sample surface.
It is clear that STM experiments require ultimate mechanical stability of the microscope. The smallest vibration of the tip against the surface will disturb the experiment. Although scanning tunnelling microscopes are constructed in a way to mimimize their susceptibilty to mechanical vibrations, for the most demanding applications it is still necessary to shield the microscope from the detrimental influence of sound and floor vibrations. For this purpose we have designed two specially shielded rooms in our Ultra-Low Vibration STM Laboratory.
The Ultra-Low Vibration STM Laboratory is based on a room-in-room concept. Two sound-proof and electromagnetically shielded rooms that house one STM each are located in a hall from where the microscopes are operated. Each room is built on a 100-ton concrete foundation that floats on passive air dampers and is therfore decoupled from the surrounding building. The large mass of the foundations ensures a low mechanical resonance frequency (below 1 Hz), thereby offering optimum vibration-insulation of the microscopes in the rooms.
Contact: F. S. Tautz