Ultra small InAs/GaInP/InP quantum dots [MOMBE growth]

InAs quantum dots were grown on tensile strained Ga_xIn_1-xP layers having a Ga content between x=0 to x=0.3, on InP substrates. The vertical dimension of these quantum dots is demonstrated to be just 2 to 8 monolayers. The PL emission is composed of distinct peaks, each peak attributed to quantum dots having the same height. The size distribution of the quantum dots depends on their growth time, as well as on the Ga content in the strained Ga_xIn_1-xP layer underneath. A comparison between an 8 band k·P model and the measured energy levels, reveals that Ga atoms diffused from the Ga_xIn_1-xP layer into the quantum dots. The Ga concentration in the quantum dots reached 19%, for dots grown on Ga_0.3In_0.7P.