We study numerically and analytically the properties of the stationary state of a particle moving under the influence of an electric field E in a two dimensional periodic Lorentz gas with the energy kept constant by a Gaussian thermostat. Numerically the current appears to be a continuous function of E whose derivative varies very irregularly, possibly in a discontinuous manner. We argue for the non differentiability of the current as a function of E utilizing a symbolic description of the dynamics based on the discontinuities of the collision map. The decay of correlations and the behavior of the diffusion constant are also investigated.
All Science Journal Classification (ASJC) codes
- Statistical and Nonlinear Physics
- Mathematical Physics
- Steady state current
- Symbolic dynamics
- Thermostatted Lorentz gas