Microfields in stroboscopic voltage measurements via electron emission. I. Response function of the potential energy

It is shown that the response of the electrostatic potential on voltage changes at a conducting line in a microscopic structure is fully described by a pure geometry function. This function is determined by the special microscopic character of the conducting line and by the screening due to neighboring conductors. It already allows a qualitative description of transit-time and cross-talk effects in voltage measurements via electron emission or electro-optical sampling, and provides a basis for the quantitative calculation of these effects. The geometry dependence of this function will be analyzed in detail.