Semiconductor Quantum Materials

Sophisticated molecular beam epitaxy techniques are the most powerful tools for the fabrication of highest-purity III/V-semiconductor heterostructures. The group's main focus lies on the study of novel quantum phases in low-dimensional systems. In the GaAs/AlGaAs material system these form at very low temperatures when the sample containing a two-dimensional electron system (2DES) of ultrahigh mobility is exposed to a strong magnetic field and (fractional) quantum Hall effect phases form. In a new effort, InAs/Al(Ga)Sb-based systems are fabricated and investigated. For these structures with broken band alignment, a tunable topological insulator is predicted. In addition, the group supplies highest-quality and tailored 2DESs for a large number of experimental groups in house as well as at other universities and in industry worldwide.