High Energy Excitations in CdSe Quantum Rods

The plane-wave pseudopotential method is used to calculate the high energy exciton states of large CdSe quantum rods, including spin−orbital coupling and screened electron−hole Coulomb interaction. Theoretical ground exciton energies of colloidal CdSe quanutm rods and wires are in good agreement with recent experiment. In addition to photoluminescence spectra, our results also show strong polarization in the absorption spectra of quantum rods, in contrast to spherical quantum dots. The absorption peaks as functions of the ground exciton energy are compared with experimental results.