Atomically sharp, crystal phase defined GaAs quantum dots

Abstract

Crystal phase defined heterostructures, or polytype heterostructures, are atomically sharp with no intermixing, which makes them ideal contenders for a wide range of applications. Although polytype quantum dots have shown promising results as single photon sources, a high degree of control on the dimensions and the number of polytype quantum dots is necessary before any application can be developed. In this work, we show results from optical characterization of highly controlled wurtzite (wz)–zinc blende (zb) GaAs quantum dots with sharp photoluminescence signal and a strong indication of 0D density of states. One band effective mass calculations show good agreement with the measured data. Radially confined nanowires with a single wz–zb GaAs interface also show sharp photoluminescence signal and 0D density of states. This indicates the existence of quantum dot like states in triangular wells formed at the wz–zb GaAs interface. These results show the potential of polytype quantum dots for physics and optics applications.