Localized DC Field Produced by Diode Implanted in Isotropic Homogeneous Medium and Exposed to Uniform RF Field

Minimally invasive selective stimulation of biological tissue within the body can be achieved by implanting a small rectifying diode and then applying an RF field by means of electrodes or a coil on or near the surface of the body. A theoretical analysis of a simplified model consisting of a cylindrically symmetrical unit implanted in an isotropic homogeneous medium of conductivity σand permittivity ϵ and exposed to a uniform RF field relates the dc component of electrode current to the detailed geometry of the electrodes of the implanted unit and to the amplitude of the applied field.