Avoiding induced heating in optical trap

Abstract

Luminescence of a single upconverting particle (NaYF 4 :Er 3+ ,Yb 3+ ) can be used to determine the optical trap temperature due to the partial absorption of the trapping beam either by the medium (water) or the optically trapped particle itself. This fact is an important drawback can be reduced by shifting the trapping wavelength out of the water absorption band, or by using time-modulated laser trapping beams. Both approaches have been studied and the results have shown that the thermal loading due to the trapping radiation can be minimized.