St-Onge D A, Sydora R D
Department of Physics, University of Alberta, Edmonton, Alberta, Canada T6G 2E1.
Phys Rev E Stat Nonlin Soft Matter Phys. 2014 Sep;90(3):033103. doi: 10.1103/PhysRevE.90.033103. Epub 2014 Sep 2.
The complete Kubo conductivity tensor is computed in two- and three-dimensional linear magnetic null systems using collisionless single-particle simulations. Regions of chaotic charged-particle dynamics are constructed for each case. It is found that stochastic frequency mixing of particle bounce motion, as well as gyromotion, contribute significantly to the conductivity. The conductivity curves are well approximated by power laws over a certain frequency range and the ac conductivity is found to be an order of magnitude smaller than the dc value, leading to enhanced resistivity, particularly near the cyclotron frequency. The ac conductivities must be accounted for in computation of the total dissipation.
