Wahl P, Diekhöner L, Schneider M A, Kern K
Max-Planck-Institut für Festkörperforschung, Heisenbergstr. 1, D-70569 Stuttgart, Germany.
Rev Sci Instrum. 2008 Apr;79(4):043104. doi: 10.1063/1.2907533.
Scanning tunneling spectroscopy has developed into a powerful spectroscopic technique that has found wide application in the atomic scale characterization of the electronic properties of clean surfaces as well as adsorbates and defects at surfaces. However, it still lacks the standard methods for data treatment and removal of artifacts in spectra as they are, e.g., common in photoemission spectroscopy. The properties of the atomic scale tip apex--the probe of the instrument--tend to introduce spurious background signals into tunneling spectra. We present and discuss two methods which permit to extract tip-independent information from low temperature tunneling spectra acquired on single atoms and molecules on single crystal surfaces by background subtraction. The methods rely on a characterization of the tip on the clean metal surface. The performance of both methods is demonstrated and compared for simulated and experimental tunneling spectra.
扫描隧道光谱已发展成为一种强大的光谱技术，在清洁表面以及表面吸附物和缺陷的电子性质的原子尺度表征中得到了广泛应用。然而，它仍然缺乏像光电子能谱中常见的那样用于数据处理和去除光谱伪像的标准方法。原子尺度的针尖顶端——仪器的探针——的特性往往会在隧道光谱中引入虚假的背景信号。我们提出并讨论了两种方法，这两种方法可以通过背景扣除从在单晶表面的单个原子和分子上获得的低温隧道光谱中提取与针尖无关的信息。这些方法依赖于对清洁金属表面上的针尖的表征。针对模拟和实验隧道光谱展示并比较了这两种方法的性能。
