DEPARTMENT OF
PHYSICAL CHEMISTRY
DEPARTMENT OF
PHYSICAL CHEMISTRY
THz Scanning Tunnelling Microscopy

We employ visible to infrared ultrashort laser pulses for photoexcitation of the STM. Subsequent gating of the tunnel junction by ultrabroadband single-cycle THz-pulses allows for the local probing of the photoexcited state, providing new insight into the atomic-scale variations of the dynamics of charge carriers. Moreover, the application of a quasi-static femtosecond voltage pulse via THz-pulse excitation of the tunnel junction allows for the ultrafast injection of electrons into otherwise inaccessible electronic states. THz-controlled femtosecond electron injection in the STM, thus, provides a tool for probing ultrafast electronic and optoelectronic processes on the nanometer scale and below.