Cadmium Selenide Quantum Wires and the Transition from 3D to 2D Confinement.

The recent availability of semiconductor nanocrystals having anisotropic rod, wire, arrow, teardrop and tetrapod morphologies has renewed interest in how shape affects the electronic and optical properties of quantum nanostructures. The article discusses the size dependence of the band gaps in cadmiumselenide quantum wires and compares it to the corresponding size dependences in cadmiumselenide quantum dots and rods. It shows that the experimentally measured quantum wire band gaps are consistent with theoretical predictions, confirming that geometric dimensionality influences quantum confinement as expected. Our results quantify true 2-dimensional quantum confinement in the well-studied cadmiumselenide system.