Hall conductance of dilute electrolytes from odd stochastic density functional theory

Abstract

Electrolytes under an external magnetic field exhibit a Hall conductivity, much like metals and semiconductors. However, existing theories fail to quantitatively account for their measured Hall conductivities. To make progress toward such a theory, we develop a stochastic density functional framework for electrolytes in a magnetic field. This framework, which we dub odd SDFT, extends the celebrated stochastic density functional theory (SDFT) to incorporate transverse mobilities and chiral time-correlated noise. Using this framework, we calculate the Hall conductivity in the absence of hydrodynamic solvent effects through three approaches: (i) direct response, (ii) Green-Kubo relation, and (iii) a hybrid fluctuation-dissipation relation. We further show that odd SDFT applies more broadly to fluids with broken time-reversal and mirror symmetry, including odd-diffusive fluids and chiral active matter. Our results generalize the relaxation correction of Debye-Hückel-Onsager theory to magnetized electrolytes and provide a foundation for incorporating additional effects mediated by the solvent that could quantitatively reconcile theory and experiments.