Mesh-based electric field

In a second step the mesh based electric field E rp) is calculated by taking the derivative of the electrostatic potential. In P M, this is done by simply... 

In a second step the mesh-based electric field E(rp) is calculated. Basically, the electric field is the derivative of the electrostatic potential, but there exist several alternatives for implementing the differentiation on a lattice [10]. Here we will restrict ourselves to the case of ik differentiation, which works by multiplying the Fourier-transformed potential with ik. In this case E rp) can be written as... 

FIGURE 2.2. (a) Schematic view of SCLC. With an external electric field (V/d), an additional internal field (E ) induced by injected excess charge carriers plays important role for the achievement of high current density. The total electric field, Etotai = V/d + E, significantly enhances current flow. Open symbols (o) corresponds to excess holes, closed symbols ( ) correspond to excess electrons, (b) Comparison of J—V characteristics based on ohmic current (dashed line) and SCLC (solid line). The meshed area shows the J—V requisite for practical devices. 

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