Journal of Vacuum Science & Technology B, Vol.21, No.6, 2344-2347, 2003
Electric field effects in single semiconductor quantum dots observed by scanning tunneling luminescence
Scanning tunneling microscopy (STM) and scanning tunneling luminescence were used to correlate the topography with the emission spectra from individual self-assembled, InP quantum dots (QDs). We have investigated in detail how the electric field induced by the STM tip affects the emission from the QDs. This was done when exciting a QD, by altering the bias for constant current, by altering the current for constant bias, or by changing the tip position. An increased bias (increased electric field) leads to Stark shift of the QD emission, whereas a larger tunneling current results in state filling of the emission. Furthermore, when exciting the QD, the position of the STM tip is shown to have large effects on the QD luminescence. (C) 2003 American Vacuum Society.