Dissipative split-charge formalism: Ohm's law, Nyquist noise, and non-contact friction

Abstract

The split-charge equilibration method is extended to describe dissipative charge transfer similarly as the Drude model, whereby the generic frequency-dependent dielectric permitivitties or conductivities of dielectrics and metals can be mimicked. To demonstrate the feasibility of the approach, a resistor-capacitor circuit is simulated using an all-atom representation for resistor and capacitor. The simulated dynamics reproduce the expected charging process and Nyquist noise, the latter resulting from the thermal voltages acting on individual split charges. The method bears promise to model friction caused by the motion of charged particles past metallic or highly polarizable media.