Statistical approach for the ensemble of quantum dots on GaAs(001)

It is shown that Stranski-Krastanov transition, i. e. the change of the growth mode from 2D to 3D in the formation of InAs quantum dots on (001) GaAs is actually a two-dimensional phase transition in the lattice-gas model. The density of lattice gas in quantum dots ensemble changes abruptly from low to high value corresponding to the liquid of quantum dots. The lateral interaction has a decisive role in the phase transition; its parameters are defined. In spite of repulsive direct pair potential of quantum dots interaction the indirect interaction leads to effective attraction between the quantum dots, which results in their condensation.