Application of low-temperature scanning electron microscopy to superconductors

Scanning electron microscopy applied to specimens in close thermal contact with a liquid-helium bath can be used for a two-dimensional display of various sample responses arising from the localized excitation of the sample by the electron beam. As shown in recent experiments, the method becomes particularly interesting when applied to superconductors. A general response theory is outlined, and a detailed treatment is given for the special case of the thermal response associated with a strongly temperature-dependent electrical resistance of the sample.