The electron-phonon mean free path in potassium: a comparative study of radio frequency size effect measurement techniques

Abstract

Previous radio frequency size effect measurements in potassium have suggested that (1/lep)eff, the effective inverse electron-phonon mean free path, depends upon the mode of RF excitation employed in the experiment. The authors report new measurements, made using both bilateral and unilateral excitation, which show that (1/lep)eff is not affected by the mode of excitation. This result is supported by simple physical arguments and confirmed by a numerical calculation. It was impossible, however, to resolve the discrepancy between the value of (1/lep)eff measured in this work and that measured by Tsoi and Gantmakher (1969) and Blaney and Parsons (1970) in earlier work.