All Electronic Isolator Action Device Based on Negative Refractive   Heterostructure Bi-Crystal with Field Induced Asymmetry
  It has been discovered that heterostructure bicrystal arrangements lead to field asymmetry in guided wave structures. Here a study is conducted over a range of nominal permittivity values to see if the effect is present in widely varying dielectric materials. Marked shifts of the field distribution occurs in some cases, and this can be the basis of an all electronic isolator. Such an all electronic device could be fixed or even constructed as a control component using materials with electrostatically controllable permittivity. Distributions have been obtained to demonstrate the effect using an anisotropic Green's function solver. 
Clifford M. Krowne