%0 Journal Article %T Fluorescence correlation spectroscopy in laser gradient field %A Fanbo Meng %A Bo Chen %A Yao Ding %A Hui Ma %A Lei Jin %A Dieyan Chen %J Chinese Science Bulletin %@ 1861-9541 %D 2001 %I %R 10.1007/BF02900611 %X Fluorescence correlation spectroscopy (FCS) is capable of probing dynamic processes in living biological systems. From photon fluctuation of fluorescing particles which diffuse through a small detection volume, FCS reveals information on the concentration and the structure of the particles, as well as information on microscopic environment. In this note, we study the radiation forces experienced by Rayleigh particles in a laser field in details, and analyze the effects of gradient field on FCS measurements. %K fluorescence correlation spectroscopy %K gradient field %K Brownian motion two-photon fluorescence %U http://link.springer.com/article/10.1007/BF02900611