4K Laboratory

This facility was built from scratch starting in 2004. On top of an optical table, supported by air springs, resides a two chamber UHV system. One chamber is equipped with a vertical transfer system to insert samples and tips into the STM. The other chamber is used for sample preparation. It features an ion gun, sample heaters, and two electron beam evaporators. There is also a load lock attached for introducing new samples.

Concept of the 4K system: full expansion with
3 chamber UHV system.
Current status of the 4K lab

The STM is a home built version of a Pan-style microscope. The samples are mounted on a sample stud and loaded from the top. The tip sits in a tip cup on top of the scan piezo. The piezo is mounted inside a sapphire prism held by six shear piezo stacks used for coarse approach.

Picture of the STM Schematic of the STM (cross section)

The STM is mounted via gold plated copper rods inside a vacuum can. The can is submersed in liquid He and sits inside the bore of a 9 T electromagnet.

STM mounted on probe