representation of a parallel plate sandwich structure in which the insulating layer 103 containing the nanoparticles 102 separates the two electrodes 101 and 104 the structure is realized on a substrate 100 the electric power source and connections 105 are applied to create a potential difference between the electrodes 101 104 and to induce electrode 106 formation to the nanoparticles 102 irreversible structural transformation leading to electrical conductivity as explained in detail below many metal oxides such as titanium oxides exhibit high dielectric permittivity typically u2208 r u02dc 100 or more in contrast the typical insulating u201c filler u201d materials have dielectric permittivity significantly smaller u2208 r u02dc 10 or below therefore as depicted in fig2 the series capacitance cs induced by the filler effectively screens the nanoparticle 102 from experiencing the full electric field created between the electrodes 101 104 the structure in fig2 is a simplified geometry based on a single nanoparticle with the series capactitances c s and the effective nanoparticle capacitance c n indicated fig3 and 4 further illustrate the shielding effect based on the results of an electrostatic finite element method simulation assuming u2208 r u02dc 100 for the nanoparticle and u2208 r u02dc 10 for the filler material the electrostatic potential.