  The equivalent circuit simulation of random resistors-capacitors (R-C) net,
modified to include large capacitors interfacing between the random R-C bulk
and the electrode surface, shows an enhancement of 3 orders of magnitude of the
apparent real dielectric constant at low frequencies upon an introduction of
resistors percolating paths in the bulk. The appearance of the bulk
R-percolating paths can represent the photo-generated high conductivity state
of semiconductors bulk, an effect supported by the experimental observation
that, in parallel with the photo-enhancement of the real dielectric constant,
its imaginary part is strongly enhanced as well. The addition of the
photo-generated charge carriers strongly enhances bulks electrical
conductivity, effectively confining the space charge region to the interface
between bulks edge and the electrode. That could be a simple phenomenological
explanation for the apparent dielectric constant enhancement upon illumination
in photocells, not involving elaborate physical models.
