Studies of enhanced field emission relevant to high field superconducting radio frequency devices

Surface roughness represents the measure of irregularities on surface contributing to local field enhancement. The traditional Fowler-Nordheim equation established for perfectly planar surfaces is not suitable describing emission from rough surfaces. Instead, it more appropriate use that accounts enhancement factor effect morphology. In superconducting radio frequency cavities, may occur in irises while tips cavity act as an emitter leading high electric field. For this study, calculations hemispherical, cylindrical, and conical have been performed using a Multiphysics software package COMSOL. focus was put dependence shape radius protrusions. strength current density increase with increasing root mean square average profile heights due at irises. lowest value has achieved hemisphere. calculated values factors are consistent data literature, which case protrusion represent small bump cavity. Based fit results, presented here, relation between suggested. accurate estimation play crucial role design accelerators other technological applications requirements extremely precision.