Temperature at the focal point of optical trapping beam: evaluation using fluorescence correlation spectroscopy

摘要

Fluorescence correlation spectroscopy was applied to the evaluation of the local heating at the focal spot of near-infrared laser for optical trapping. Based on the translational diffusion coefficient of probe dyes at the focal spot in solution, the relation between temperature rise and incident laser power, △T/△P, were determined for water, ethylene glycol, l-pentanol, lhexanol, l-octanol, l-nonanol, and l-decanol. The value of △T/△P linearly increased with a/l(a and l is the absorption coefficient and thermal conductivity of solvent, respectively) as predicted by a simple theoretical model.