Field-emission resonance measurements with mechanically controlled break junctions

The additional information provided by field emission resonance spectra significantly increases the potential of the mechanically controllable break junction technique. We have found that the pronounced three-dimensional nature of the electrodes results in an extremely high sensitivity of the field emission resonance spectra to the fine details of the surface geometry, electronic structure and electric field distribution at small electrode separations. At larger distances a quasiclassical approximation can be used for the determination of the metal work function, precise calibration of the electrode relative displacement and discrimination between “blunt” and “sharp” electrodes on the basis of the distance–voltage z ( V ) dependence.