Influence of the characteristics of the STM-tip on the electroluminescence spectra

We analyze the influence of the characteristics of the STM-tip (applied voltage, tip radius) on the electroluminescence spectra from an STM-tip-induced quantum dot. We find that positions of electroluminescence peaks, attributed to the electron-hole recombination in the quantum dot, are very sensitive to the characteristics of the tip, namely increasing voltage on the STM-tip results in a red shift of the electroluminescence peaks, while the peak positions as a function of the tip radius reveal a non-monotonous behavior.