Spilling of electronic states in Pb quantum wells

Article

关键词: SCANNING-TUNNELING-MICROSCOPY;    ULTRATHIN METALLIC-FILMS;    BY-LAYER GROWTH;    THIN-FILMS;    LOW-TEMPERATURES;    LEAD FILMS;    SIZE;    SURFACE;    OSCILLATIONS;    PHOTOEMISSION;   

DOI  :  10.1103/PhysRevB.93.035437

来源: SCIE

【 摘 要 】

Energy-dependent apparent step heights of two-dimensional ultrathin Pb islands grown on the Si(111)6 x 6-Au surface have been investigated by a combination of scanning tunneling microscopy, first-principles density-functional theory, and the particle-in-a-box model calculations. The apparent step height shows the thicknessand energy-dependent oscillatory behaviors, which are directly related to the spilling of electron states into the vacuum exhibiting a quantum size effect. This has been unambiguously proven by extensive first-principles scanning tunneling microscopy and spectroscopy simulations. An electronic contribution to the apparent step height is directly determined. At certain energies it reaches values as high as a half of the atomic contribution. The applicability of the particle-in-a-box model to the spilling of electron states is also discussed.

【 授权许可】

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