Numerical investigation of electrostatic interactions in nanoscale substances based on finite-size particle simulation

We use the optimized finite-size particle techniques derived from plasma simulations to investigate the electrostatic interactions in nanoscale substances. In conjunction with electron tunneling, the substance surface is modeled as a potential well that confines simulated electrons for reaching equilibrium in an electrostatic system governed by Poisson's equation. This scheme avoids the mathematical difficulty of handling sophisticated boundary conditions at the interface and easily treats complicated shapes. We demonstrate the performance of the proposed method by simulating millions of electrons propagating in isolated substances at nanoscale. Numerical results are consistent with theoretical predictions of electrostatic properties in equilibrium.