Point-contact spectroscopy in alkali metals: K, Na and Li

Abstract
The current-voltage characteristics of point contacts of the alkali metals K, Na and Li have been studied experimentally at liquid-helium temperatures. The observed structures in the spectra (d2V/dI2) measured as a function of the applied voltage are in agreement with the structures of the phonon densities of states, and confirm pseudopotential calculations of the electron-phonon interaction parameter.