Influence of substrate orientation on InAs/GaAsquantum-dot growth studied by photoluminescence inpulsed magnetic fields

摘要

By using photoluminescence spectroscopy in very high magnetic fields (<50 tesla) we have investigated the dependence of InAs quantum dot formation on the GaAs substrate orientation. For InAs deposited on (100)-oriented GaAs, an abrupt change from one-dimensional to three-dimensional charge confinement is observed. On substrates cleaved along the (311)B axis, there is a much weaker charge confinement that gradually increases with the amount of InAs deposited. At the highest coverage studied (1.9 monolayers), the quantum-dot confinement is equally effective for both substrate orientations.