Comment on 'Phase Contribution of Image Potential on Empty Quantum Well States in Pb Islands on the Cu(111) Surface'

摘要

The Letter by Yang et al. [1] presents an experimental scanning tunneling spectroscopy (STS) study of unoccupied quantum well states (QWSs) in Pb islands grown on the Cu(111) surface. The departure from particle-in-a-box energy dispersion has been observed with decreasing energy spacing between QWSs for the energies above 3 eV with respect to the Fermi level (E_F).