Dynamical friction in sliding condensed-matter systems

Abstract

A many-body system sliding at constant center-of-mass velocity relative to an external periodic potential (e.g., due to the channels in which the ions move in an ionic conductor) is studied as a possible model for dynamical friction and as a model for electrical conduction in superionic conductors and systems containing charge-density waves. The damping force is found to all orders in the center-of-mass velocity by calculating the lowest-order response to the external periodic potential (valid if this potential is weak) via the conventional fluctuation-dissipation theorem. This permits us to calculate nonlinear electrical conduction in the charge-density wave and superionic-conductor applications of the model.