Critical size for localization of the L-like conduction states in InAs quantum dots grown on GaAs

The localization of the L-like conduction states is found to change from th e islands to the substrate in InAs quantum dots grown on GaAs as the island -size decreases. This is due to a size-induced modification of the strain s tate of the islands. The critical size should correspond to dislocation for mation. As a result, small InAs islands coherently strained to GaAs exhibit optical properties markedly different from those of bulk InAs. (C) 2000 Am erican Institute of Physics. [S0003-6951(00)03920-6].