Photoinduced Mass Transport by One-Dimensional Gaussian Beam Irradiation: Width and Polarization Dependence

Abstract

Photoinduced mass transport dynamics for the irradiation of a one-dimensional (1D) Gaussian beam was investigated experimentally, and its width and polarization dependence were simulated according to our two models. One of our models is based on viscous fluid mechanics, in which the analytical function expressing the nature of the driving force of photoinduced mass transport has been defined a priori to suit the phenomenological characteristics. Antithetically, another newly developed model assumes that the force of mass transport could be attributed to electromagnetic interaction between dipoles of the molecules and the electromagnetic field of the excitation beam, and surface tension. The polymer is treated as a viscous fluid even in the new model, but the condition of inhomogeneous viscosity that depends on the irradiated light intensity has been additionally introduced in order to describe the phenomenon more precisely. The experimental results and the simulated results were compared and discussed from the viewpoint of the validity of the models.