Gaussian beam scattering by two parallel nonabsorbing dielectric cylinders: displacement and rotational degrees of freedom

An extension of the problem of a moderately focussed Gaussian beam scattered by an arrangement of two parallel nonabsorbing dielectric cylinders of arbitrary refraction indexes and radii is developed. The feature introduced in the present solution is the relative angular position coordinate between the two cylinders (phi(0)) as a degree of freedom. Explicit dependence on this variable of scattering coefficients, beam shape coefficient, and extinction efficiency is given. Togetber with the displacement coordinate d, various other scattering configurations can be studied. The applicability of the solution is given in the form of extinction curves taking phi(0) as the main parameter for variation. The model is proposed as a means of investigating evanescent wave microscopy. (C) 2008 Optical Society of America