We report Kerr nonlinearity due to intersubband transitions in a three-level InAs/GaAs domeshaped quantum dots (QDs) system. The impact of wetting layer and dot size on the electronic, linear and nonlinear optical properties is discussed. The results showed an overall shift of dispersion curves towards lower frequencies, pronounced reshaping of absorption and dispersion curves, and two orders of magnitude enhancement in Kerr nonlinearity due to the presence of a wetting layer.
