Quantum spin Hall effect in HgTe quantum well structures

Spin polarization, manipulation and detection are the most challenging topics in current semiconductor research. Apart from the use of magnetic materials spin obit effects have become a promising alternative especially for the use of electric fields to control spin currents and polarizations. Recently, we demonstrated a new type of spin selective transport which exists in semiconductor structures with an inverted subband ordering. Due to a very strong spin orbit splitting HgTe is a prototype material for the experimental observation of this so-called quantum spin Hall effect. In this talk I present the fundamental experimental observations of the quantum spin Hall effect (QSHE). I discuss the limits of its stability and considerations for an application as injector and detector for spin polarized currents.