Nanoscale Distortions of Si Quantum Wells in Si/SiGe Quantum‐Electronic Heterostructures

Si quantum wells on plastically relaxed SiGe substrates have nanometer variations in crystallographic parameters crucial to quantum‐information devices . Synchrotron X‐ray nanodiffraction shows that the lattice of the Si quantum well varies in orientation and thickness over lateral distances of 100 nm to 1 μm. The result is that the energy levels of the confined states are shifted by energies similar to the electron temperature.