Light scattering on ultrathin capillaries

In recent experiments, very low amplitudes of Light scattering were reporte d for a tightly focused laser beam on a glass microcapillary. This result m ay be of great importance for single molecule detection in liquids. In the present paper, a theoretical study of the problem of Light scattering of a focused laser beam on a cylindrical glass capillary is given. The numerical calculations are based on an exact electrodynamic treatment of the whole p roblem, including vector effects of the electromagnetic field of the laser beam. It is shown that under favorite conditions (inner and outer radius of the capillary, perfect adjustment of the laser beam) the intensity of the back-scattered light may be extremely low. (C) 1999 Elsevier Science B.V. A ll rights reserved.