Self-organization of sub-micron particles in the colloidal suspensions is an attractive phenomenon in the manufacture of photonic crystals. In this report, we carry out Monte Carlo simulations of the self-arrangement of particles under the illumination of the focused laser beam. It is based on the Metropolis algorithm with a periodic boundary condition for a canonical ensemble. The radiation pressure in the focused laser beam and the interaction induced by both the van der Waals attraction and the screened Coulomb repulsion exerted between particles are taking into account. Because the simulations are restricted to the two-dimensional space, the radiation pressure is approximated to a gradient force that makes to move particles into the area with the stronger intensity. We successfully show that particles are gathered into the illuminating area by the gradient force of the focused laser beam and spontaneously organize the periodic structure. On the other hand, the periodic structure is not organized under the weak radiation pressure though the particles are gathered into the illuminated area.

Date Published: 30 October 2001
PDF: 6 pages
Proc. SPIE 4598, Photonics Technology in the 21st Century, (30 October 2001); doi: 10.1117/12.447094

Published in SPIE Proceedings Vol. 4598:
Photonics Technology in the 21st Century
John H. Marsh; Pallab Bhattacharya; Osamu Wada, Editor(s)