Tip-induced band bending by scanning tunneling spectroscopy of the states of the tip-induced quantum dot on InAs(110)

We analyze the quantized states of the tip-induced quantum dot appearing in scanning tunneling spectroscopy (STS) on n-type InAs(110) ${(N}_D=2\mathrm{}\times {10}^{16}{\mathrm{cm}}^{\mathrm{-}3}).\mathrm{}$ STS at negative sample bias (-200–0 mV) is used to determine the state energies. The analysis of the spectra indicates that the z-quantization leads to one or two quantized states while a ladder of states due to the lateral confinement is observed. The magnetic-field dependence (0–6 T) shows the expected splitting of the first excited state in quantitative agreement with Hartree calculations. If an ionized dopant is located in the center of the quantum dot, a reduction in energy and a change in intensity of the single-particle ground state is found, which is also in quantitative agreement with Hartree calculations. The analysis of the tip-induced states can be used to reconstruct the shape of the tip-induced band bending.