We report the realization of a novel superlattice which contains a high mobility (≅ 1.1×10 5 cm 2 /V s at 4 K) degenerate electron system. The structure consists of a wide, undoped Al x Ga 1-x As well bounded by undoped (spacer) and doped layers of Al y Ga 1-y As (y≳x) on both sides. The alloy composition in the well (x) is graded in such a way as to result in a parabolic potential with an additional sinusoidal modulation superimposed on it. Once transferred into this well, the electrons screen the parabolic potential and an electron system with a modulated charge density is obtained. We present self-consistent quantum mechanical calculations of the electronic system, and report our characterization of the structure by secondary-ion mass spectrometry and magnetotransport measurements.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)