Figure 6
Dependence of the variation in monoatomic step height measured by STM, Δz, on the applied bias voltage. The red circles indicate experimental data. The black curve represents the fit of the experimental data obtained from Eq. (3). k in Eq. (3) is determined by the work function, electron energy and its effective mass. The presented best fit corresponds to an effective electron mass about 0.1me (effective mass of electrons in Sb in the [111] direction is about 0.1me45,46,47). The STM experiment was performed at bias voltages where the difference in DOS on either side of the monoatomic step is significant according to the DFT simulations (Fig. 7a).
