Evolution of the density of states from a two- to a zero-dimensional semiconductor

Zeger Hens (1) , B. Grandidier (2) , D. Deresmes (2) , Guy Allan (2) , Christophe Delerue (2) , Didier Stiévenard (2) , Daniel Vanmaekelbergh (1)

1 Universiteit Utrecht / Utrecht University [Utrecht]
2 IEMN - Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520

Lead selenide nanocrystals have been electrodeposited on gold(111) with a high degree of control over their dimensions, giving rise to isolated nanocrystals with different edge-to-height aspect ratio. The electron density of states (DOS) of individual nanocrystals as a function of their aspect ratio is studied in the regime of strong quantum confinement by electron tunnelling spectroscopy. We find a broad transition regime, spanning the two- and zero-dimensional geometry, where the DOS function has a rich and variable structure, featuring steps and peaks. The experimental results are supported by electronic-structure calculations.

Domaines: Sciences de l'ingénieur [physics]

Zeger Hens, B. Grandidier, D. Deresmes, Guy Allan, Christophe Delerue, et al.. Evolution of the density of states from a two- to a zero-dimensional semiconductor. EPL - Europhysics Letters, 2004, 65, pp.809-815. ⟨10.1209/epl/i2003-10130-3⟩. ⟨hal-00141246⟩