Abstract
Scanning tunneling spectroscopy images on exhibit a strong magnetic field dependent contrast on the 50 nm length scale, indicating fluctuations in the density of states of the sample. The contrast is correlated to previously observed Landau oscillations in curves. Its origin is a spatial fluctuation of the Landau level energy of 3–4 meV caused by the inhomogeneous distribution of dopant atoms. Besides inducing large-scale fluctuations in the density of states, dopants preserve their ability to scatter electron waves. The resulting wave pattern is found to depend on the magnetic field. It is suggested that the dependence is guided by the condensation of the electronic states on Landau tubes.
- Received 14 February 2000
DOI:https://doi.org/10.1103/PhysRevLett.84.5588
©2000 American Physical Society