Boundary Conditions at Infinity for a Single Blocking Electrode

Abstract
A mathematical appraisal is made of the boundary conditions at infinity for certain space-charge problems such as the single blocking electrode. Fulfillment of the boundary condition that the potential approach a limiting value at infinity resides in an appropriately devised theorem. The validity of approximate Poisson-type differential equations can be ascertained by invoking the Jacobian. Two separate situations are considered: (1) carriers of either sign mobile, (2) positive charges fixed. The latter corresponds to a problem (first) considered by MacDonald. A new formulation for the latter proves illuminating and an asymptotic solution is deduced for the spatial variation of the potential which reflects the essential exponential nature of its behavior.

This publication has 2 references indexed in Scilit: