Effect of branching of tetrapod-shaped CdTe/CdSe nanocrystal heterostructures on their luminescence

We have studied the CdTe/CdSe tetrapod-shaped nanocrystal heterostructures with the use of photoluminescence spectra measurements and time-correlated single photon counting technique. The tetrapods were grown to have CdTe arms with different thickness of the CdSe shell. We have observed non-exponential photoluminescence decay of excited tetrapod-nanocrystals and proposed kinetic theory based on the branched crystal morphology and on the assumption about a potential barrier in the junction point of tetrapod. Analysis of studied nanocrystal behavior gives an evidence for tetrapods to behave as four weakly connected quantum wells. This interesting effect might find applications in nanoelectronics.