Effects of Crystal Shape on the Energy Levels of Zero-Dimensional PbS Quantum Dots

Z. Hens; D. Vanmaekelbergh; E. J. A. J. Stoffels; H. van Kempen

doi:10.1103/PhysRevLett.88.236803

Effects of Crystal Shape on the Energy Levels of Zero-Dimensional PbS Quantum Dots

Z. Hens, D. Vanmaekelbergh, E. J. A. J. Stoffels, and H. van Kempen

Phys. Rev. Lett. 88, 236803 – Published 24 May 2002

Abstract

Nanometer-size PbS quantum dots have been made by electrodeposition on a Au(111) substrate. The deposited nanocrystals have a flattened cubic shape. We probed the single-electron energy-level spectrum of individual quantum dots by scanning tunneling spectroscopy and found that it deviates strongly from that of spherical PbS quantum dots. The measured energy-level spectrum is successfully explained by considering strong confinement in a flattened cubic box.