CHARGE KOSTERLITZ-THOULESS TRANSITION IN THIN GRANULAR FILMS DUE TO CHARGE CONFINEMENT

A quantum electrodynamical explanation for the charge Kosterlitz-Thouless (KT) transition observed in granular films is represented by a charge-confinement model, where the effective interaction potential is logarithmic contrary to Keldyshs model, in which it is classical logarithmic. Unlike the former, the latter is suitable only under the Keldysh condition that the dielectric constant of the granular film is much larger than that of the surrounding medium. For testing the effectiveness of the two models, we propose an experiment showing the possible KT transition without the Keldysh condition. © 1995 The American Physical Society.