IONIZATION OF CHARGE-ANTICHARGE PAIRS IN ULTRATHIN PALLADIUM FILMS

Abstract

The electrical conductance and I–V characteristics of ultrathin Pd films prepared by low temperature deposition have been measured in situ. An Arrhenius behavior was found for the electrical conductance. A crossover between regimes with different activation energies was observed at a temperature TK. Below TK, the I–V characteristics of the film were found to be nonlinear. These observations are explained using a charge Kosterlitz-Thouless-Berezinskii transition picture which involves the ionization of charge-anticharge pairs.