Scientific Activities on Low-Dimensional Electron Systems
Collaboration with Klaus von Klitzing
Jürgen Weis, till 2011 group leader in the Department "Low Dimensional Electron Systems" of Klaus von Klitzing – working on electrical properties of quantum dot systems and scanning probe experiments on quantum Hall systems -, continues with a small group some scientific activities on low-dimensional electron systems: In a long lasting project we have used a low-temperature scanning force microscope operating at 1.4 K to measure the Hall potential profiles and therefore the current distribution in quantum Hall samples. In 2014 we have established a low-temperature scanning probe microscope in the Precision Lab of the Institute working in a top-loading 3He-4He dilution refrigerator below 50 mK. As probe an array of about eight single-electron transistors (SETs) is used, made in our cleanroom facility, which act as independent electrometers probing quantum Hall samples at a distance of few tens of nanometers with a resolution below 0.1 µm.
Scientific Activities on Electron Beam Lithography
Due to the request by our customers on high resolution electron-beam lithography on various substrates (silicon, III-V semiconductor heterostructures, glass, diamond, metal oxide heterostructures, plastics, …) and with diverse resists we have to look into a better understanding of electron beam lithography.