Homogenization of hydrodynamic transport in Dirac fluids

Abstract

Large-scale electrical and thermal currents in ordinary metals are well approximated by effective medium theory: global transport properties are governed by the solution to homogenized coupled diffusion equations. In some metals, including the Dirac fluid of nearly charge neutral graphene, microscopic transport is not governed by diffusion, but by a more complicated set of linearized hydrodynamic equations, which form a system of degenerate elliptic equations coupled with the Stokes equation for fluid velocity. In sufficiently inhomogeneous media, these hydrodynamic equations reduce to homogenized diffusion equations. We recast the hydrodynamic transport equations as the infimum of a functional over conserved currents and present a functional framework to model and compute the homogenized diffusion tensor relating electrical and thermal currents to charge and temperature gradients. We generalize to this system to the well-known results in homogenization theory: Tartar’s proof of local convergence to the homogenized theory in periodic and highly oscillatory media and sub-additivity of the above functional in random media with highly oscillatory, stationary, and ergodic coefficients.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jan 01, 2021
Source ID
10.1063/5.0021961

Entities

People

  • Andrew J. Lucas
  • Guillaume Bal
  • Mitchell Barry Luskin

Organizations

  • Army Research Office
  • National Science Foundation
  • Office of Naval Research Global
  • University of Chicago
  • University of Colorado
  • University of Minnesota

Tags

Readers

  • Fluid Dynamics.
  • Mathematical Modeling and Probability Theory.
  • Plasma Physics / Magnetohydrodynamics

Technology Areas

  • Microelectronics