Dielectric property of
particles at interface in random sequential adsorption and its application to
whispering gallery mode resonance-shift sensors

I. Teraoka,
and S. Arnold

J. of Appl. Phys. 101, 023505 (2007)

Dielectric properties of particles adsorbed onto a
planar interface between two dielectric media are

considered, taking into account the dipolar fields created by polarization
induced in nearby particles

as well as by their image dipoles. The use of a dipolar approximation allowed us
to derive a

self-consistent expression for the effective field experienced by each particle.
The expression uses

the pair correlation function of the particle distribution and is presented in a
close form for normal

and tangential directions of the applied field. To obtain the correlation
function for the distribution

of irreversibly adsorbed particles and calculate the effective field, a computer
simulation of random

sequential adsorption was carried out at prefixed particle densities and until
placing the next particle

became extremely difficult. The effective field was also calculated for
hexagonal closest packing.

Results of these calculations were then used to estimate resonance wavelength
shifts of whispering

gallery modes in a dielectric microsphere when it adsorbs dielectric particles.
A gradual change was

seen from the shifts for isolated particles at low densities to those for a
packed layer.