Effect of Shape Anisotropy and Size on the Electronic Structure of CdSe/ZnSe Quantum Dots

The effect of shape anisotropy and size on the electronic structure of CdSe/ZnSe quantum dots is theoretically investigated. The quantum dot is modeled by assuming a parabolic confinement along xy plane and by finite well potential due to band offset along growth (z) direction. The energy eigenvalues and wave functions of holes in multivalence band are computed by numerical diagonalization of 4 × 4 k.p Luttinger Hamiltonian. The wave functions thus obtained are used for calculating dipole matrix elements to analyze the degree of linear polarization and allowed transitions between multivalence band and conduction band. The effect of variation of dot size, dot height, and shape anisotropy factor on the electronic structure is also analyzed. We observe that the size and shape anisotropy of quantum dot play a significant role in determining their electronic structure.