High resolution photocurrent imaging by atomic force microscopy on the example of single buried InAs quantum dots

Abstract

Conductive atomic force microscopy in combination with an optical setup is a useful tool for obtaining spectrally and spatially resolved photocurrent information on photoactive nanostructures. We have demonstrated photocurrent mapping under ambient conditions using sub-surface InAs quantum dots (QDs) as an example, whereby the QDs appear as dark areas in the photocurrent signal. Spectrally resolved measurements of on-dot and off-dot areas show distinct differences, confirming the existence of QDs at the detected position.