Third-order nonlinear optical susceptibilities associated with intersubband transitions in CdSe/ZnS core–shell quantum dots

The nonlinear susceptibilities associated with intersubband transitions in the conduction band are theoretically calculated for CdSe/ZnS spherical core–shell quantum dots. The confined wave functions and eigenenergies of electrons in quantum dots have been calculated under the effective-mass approximation by solving a three-dimensional Schrödinger equation. And the third-order susceptibilities for quadratic electro–optic effects as a function of core, shell radii, relaxation time and pump photo energy involving the position of energy levels also have been analyzed.